Instructing device configured to selects a cooperating device based on a predetermined power supply reliability

ABSTRACT

A table information reception unit in an instructing device receives, from processing devices connected to a network, device names of the processing devices, function information indicating functions included in the processing devices, and power information indicating a reliability of power supply to the processing devices, and causes such information to be reflected in a table stored in a storage unit. Upon receiving a processing request from a user, an analysis unit analyzes the content thereof, transmits, to an execution control unit, requested function information indicating functions necessary to execute processing corresponding to the processing request. Based on the requested function information, the execution control unit judges whether cooperation with another processing device is necessary, and if necessary, selects, based on the table stored in the storage unit, a processing device expected to have a stable power supply to be a cooperating processing device.

TECHNICAL FIELD

The present invention relates to technology for cooperative processingamong a plurality of devices connected to a network.

BACKGROUND ART

In recent years, cooperative processing has been performed betweengeneral consumer electrical devices such as TV receivers and DVD/HDD(Hard Disk Drive) recorders that can be connected to a network. Forexample, a user can instruct a DVD/HDD recorder to perform scheduledrecording by using a remote control or the like to perform an operationon a TV receiver displaying a TV program listing.

Technology for cooperative processing among devices is disclosed in, forexample, patent documents 1 and 2. The following briefly describes thetechnology disclosed in these documents.

Patent document 1 discloses a content recording system in which aplurality of video recording devices are connected to a network. In thiscontent recording system, if a plurality of videos provided at the sametime are to be recorded by one of the video recording devices, andrecording all of the videos would exceed the recording capability of thevideo recording device, the non-operating resource of another videorecording device is utilized in performing the video recording.

Also, patent document 2 discloses a programmable controller networksystem in which a user presets candidate alternative stations for amanagement station and a priority order for the alternative stations. Ifthe management station stops operating, the alternative station havingthe highest priority among the candidate alternative stations set by theuser is selected as the alternative station.

-   Patent document 1: Japanese Patent Application Publication No.    2005-25-2402-   Patent document 2: Japanese Patent Application Publication No.    H11-346215

SUMMARY OF THE INVENTION Problems Solved by the Invention

However, the technology of patent document 1 assumes that power isreliably supplied to the video recording devices. With general consumerelectrical devices such as TV receivers and DVD/HDD recorders installedin a household etc., there is a possibility that a user will cut off thepower supply at an arbitrary timing by turning off the so-called mainpower switch provided on the device, unplugging the power cable, orturning off the power switch of a power strip.

Since patent document 1 does not take into account such cases in whichthe power supply is cut off, cooperative processing will not becompleted if the power supply to one of the devices executingcooperative processing is cut off.

According to patent document 2, if the power supply to a deviceexecuting cooperative processing is cut off, cooperative processing maybe continued by switching to an alternative device. However, it isimpossible to avoid an interruption in the cooperative processing whenswitching to the alternative device. Such an interruption in cooperativeprocessing is problematic in a case of processing that requires are highdegree of real-time capability, such as processing for recording a TVprogram transmitted from a broadcast station (cooperative processingperformed by the device receiving the TV program and the devicerecording the video).

The present invention has been achieved in view of the above problems,and an aim thereof is to provide an information processing system thatlowers the possibility of an interruption in cooperation processingamong a plurality of devices.

Means to Solve the Problems

In order to solve the above problem, one aspect of the present inventionis an information processing system including an instructing device thatinstructs execution of predetermined processing and a plurality ofprocessing devices that are able to execute the predeterminedprocessing, the instructing device including: a power informationreception unit operable to receive a plurality of power informationpieces that are in one-to-one correspondence with the plurality ofprocessing devices, each power information piece relating to powersupply of the corresponding processing device and being stored by thecorresponding processing device; a selection unit operable to select,from among the processing devices, a processing device to be instructedto execute the predetermined processing, in accordance with the powerinformation pieces received by the power information reception unit; andan instruction transmission unit operable to transmit an instruction toexecute the predetermined processing to the processing device selectedby the selection unit, and each processing device including: aninstruction reception unit operable to receive the instruction toexecute the predetermined processing transmitted by the instructingdevice; an execution unit operable to execute the predeterminedprocessing if the instruction reception unit has received theinstruction to execute the predetermined processing; and a powerinformation transmission unit operable to transmit the power informationpiece that relates to power supply to the own processing device.

According to this structure, the selection unit of the instructingdevice selects the processing device that is to be requested to executethe predetermined processing, based on power information relating to thepower supply to the processing devices. Therefore, in a case where thepower information is information indicating the reliability of powersupply, such as information indicating whether the power cable of theprocessing devices can be unplugged from the plug socket (the poweroutlet), selecting the processing device that has a high power supplyreliability enables lowering the possibility that the execution of thepredetermined processing will be interrupted due to the power supply tothe processing device being cut off.

Effects of the Invention

Also, the power information transmission unit of each processing devicemay include: a storage subunit storing therein the power informationpiece relating to the own processing device; a detection subunitoperable to detect a change in a state of power supply to the ownprocessing device; and an update subunit operable to, each time thedetection subunit detects a change in the state of power supply, updatethe power information piece stored in the storage subunit so that aresult of the detection is reflected in said power information piece,and if the update unit has updated the power information piece, thepower information transmission unit may transmit the updated powerinformation piece.

According to this structure, each time a change in the power supplystate is detected by the detection subunit, the update subunit of thepower information transmission unit performs an update to cause thedetection result to be reflected in the power information, and if thepower information has been updated by the update subunit, the powerinformation transmission unit transmits the updated power information.This structure enables selecting a processing device based on powerinformation that reflects the detection result pertaining to the mostrecent detection result in the processing devices.

Also, each time a change in the power supply state is detected by thedetection subunit, the update subunit of the power informationtransmission unit performs an update to cause the detection result to bereflected in the power information, thereby enabling the instructingdevice to select a processing device without burdening the users of theprocessing devices with setting the power information in advance.

Also, each power information piece may include a cut-off countindicating the number of times that power supply to the own processingdevice has been cut off, the detection subunit of the power informationtransmission unit may detect a start of power supply to the ownprocessing device, the update subunit of the power informationtransmission unit may increment the cut-off count by one each time thedetection subunit performs the detection, and the selection unit of theinstructing device may select the processing device to be instructed toexecute the predetermined processing, in accordance with the cut-offcounts received by the power information reception unit of theinstructing device.

According to this structure, each time the detection subunit of thepower information transmission unit detects the beginning of the powersupply to the own device, the update subunit of the power informationtransmission unit increments the cut-off count in the power informationby one. Therefore, if the selection unit of the instructing deviceselects the processing device that, for example, has the lowest cut-offcount or a cut-off count that is less than a predetermined referencecount, it is possible to lower the possibility that the execution of thepredetermined processing will be interrupted due to the power supply tothe processing device being cut off.

Also, each processing device may further include a main power supplycontrol unit operable to (i) switch between a supply state of supplyingpower from an alternating current power supply to the execution unit anda cut-off state of cutting off power from the alternating current powersupply to the execution unit, and (ii) identify one of the supply stateand the cut-off state, each power information piece may include analternating current power supply cut-off count indicating the number oftimes that power supply from the alternating current power supply to theown processing device has been cut off, the detection subunit of thepower information transmission unit may detect a start of power supplyfrom the alternating current power supply to the own processing device,the update subunit of the power information transmission unit mayincrement the alternating current power supply cut-off count by one eachtime the detection subunit performs the detection while the main powersupply control unit is identifying the supply state, and the selectionunit of the instructing device may select the processing device to beinstructed to execute the predetermined processing, in accordance withthe alternating current power supply cut-off counts received by thepower information reception unit of the instructing device.

According to this structure, the update subunit of the power informationtransmission unit increments the alternating current cut-off count byone each time the detection subunit performs the detection when the mainpower supply control unit enters the supply state. Therefore, thealternating current cut-off count indicates the number of times thatpower supply from the alternating current power supply has been cut offwhile power was being supplied to the execution unit of the processingdevice, that is to say, the number of times that the power supply to theexecution unit has been cut off due to, for example, the power cablebeing unplugged from the power outlet. Accordingly, if the selectionunit of the instructing device selects the processing device that, forexample, has the lowest alternating current cut-off count or analternating current cut-off count that is less than a predeterminedreference count, it is possible to lower the possibility that theexecution of the predetermined processing will be interrupted due to thepower supply to the processing device being cut off.

Also, the main power supply control unit may be further operable tomeasure a time during which the cut-off state is being identified, eachpower information piece may further include a main power supply cut-offtime indicating the time during which the main power supply control isidentifying the cut-off state, each time the main power supply controlunit switches from the cut-off state to the supply state while thedetection subunit has not performed the detection, the update subunit ofthe power information transmission unit may add, to the main powersupply cut-off time, the time measured by the main power supply controlunit, and the selection unit of the instructing device may select theprocessing device to be instructed to execute the predeterminedprocessing, furthermore in accordance with the main power supply cut-offtimes received by the power information reception unit of theinstructing device.

According to this structure, each time the main power supply controlunit of the processing device switches from the cut-off state, in whichthe detection subunit has not performed the detection, to the supplystate, the update subunit of the power information transmission unitadds, to the main power supply cut-off time in the power information,the time measured by the main power supply control unit. Therefore, themain power supply cut-off time indicates the time for which the powersupply to the execution unit has been cut off due to the main powersupply control unit switching to the cut-off state while the powersupply is being supplied from the alternating current power supply.Accordingly, if the selection unit of the instructing device selects theprocessing device that, for example, has the lowest alternating currentcut-off count or an alternating current cut-off count that is less thana predetermined reference count, and has the longest main power supplycut-off time or a main power supply cut-off time that is longer than apredetermined reference time, it is possible to lower the possibilitythat the execution of the predetermined processing will be interrupteddue to the power supply to the processing device being cut off.

Also, each processing device may further include a main power supplycontrol unit operable to (i) switch between a supply state of supplyingpower from an alternating current power supply to the execution unit anda cut-off state of cutting off power from the alternating current powersupply to the execution unit, and (ii) identify one of the supply stateand the cut-off state, each power information piece may include a mainpower supply cut-off count indicating the number of times that powersupply has been cut off by the switching performed by the main powersupply control unit, the detection subunit of the power informationtransmission unit may detect a start of power supply from thealternating current power supply to the own processing device, each timethe main power supply control unit switches from the cut-off state tothe supply state while the detection subunit has not performed thedetection, the update subunit of the power information transmission unitmay increment the main power supply cut-off count by one, and theselection unit of the instructing device may select the processingdevice to be instructed to execute the predetermined processing, inaccordance with the main power supply cut-off counts received by thepower information reception unit of the instructing device.

According to this structure, each time the main power supply controlunit of the processing device switches from the cut-off state, in whichthe detection subunit of the power information transmission unit has notperformed the detection, to the supply state, the update subunit of thepower information transmission unit increments the main power supplycut-off count in the power information by one. Therefore, the main powersupply cut-off count indicates the number of times that the power supplyto the execution unit has been cut off due to the main power supplycontrol unit switching to the cut-off state while the power supply isbeing supplied from the alternating current power supply. Accordingly,if the selection unit of the instructing device selects the processingdevice that, for example, has the lowest main power supply currentcut-off count or a main power supply cut-off count that is less than apredetermined reference count, it is possible to lower the possibilitythat the execution of the predetermined processing will be interrupteddue to the power supply to the processing device being cut off.

Also, the execution unit of each processing device may be furtheroperable to identify whether the predetermined processing is beingexecuted, each power information piece may include a mid-executioncut-off count indicating the number of times that power supply to theown processing device has been cut off while the execution unit isexecuting the predetermined processing, the detection subunit of thepower information transmission unit may detect a start of power supplyto the own processing device, the update subunit of the powerinformation transmission unit may increment the mid-execution cut-offcount by one each time the detection subunit performs the detectionwhile the execution unit is executing the predetermined processing, andthe selection unit of the instructing device may select the processingdevice to be instructed to execute the predetermined processing, inaccordance with the mid-execution cut-off counts received by the powerinformation reception unit of the instructing device.

According to this structure, the update subunit of the power informationtransmission unit increments the mid-execution cut-off count by one eachtime the detection subunit of the power information transmission unitperforms the detection while the execution unit of the processing deviceis executing the predetermined processing. Therefore, if the selectionunit of the instructing device selects the processing device that, forexample, has the lowest mid-execution cut-off count or a mid-executioncut-off count that is less than a predetermined reference count, it ispossible to lower the possibility that the execution of thepredetermined processing will be interrupted due to the power supply tothe processing device being cut off.

Also, each processing device may further include a clock unit operableto measure a time during which the own processing device is operatingand store therein the measured time, each power information piece mayinclude an average operation time of the own processing device withrespect to a predetermined duration, the detection subunit of the powerinformation transmission unit may detect a start of power supply to theown processing device, each time the detection subunit performs thedetection, the update subunit of the power information transmission unitmay update the average operation time so that the time stored by theclock unit is reflected in the average operation time, and the selectionunit of the instructing device may select the processing device to beinstructed to execute the predetermined processing, in accordance withthe average operation times received by the power information receptionunit of the instructing device.

According to this structure, each time the detection subunit of thepower information transmission unit performs the detection, the updatesubunit of the power information transmission unit updates the averageoperation time so that the operating time stored by the clock unit ofthe processing device, that is to say the operating time of the previouscase of operation, is reflected in the average operation time in thepower information. Therefore, if the selection unit of the instructingdevice selects the processing device that, for example, has the longestaverage operation time or an average operation time that is longer thana predetermined reference time, it is possible to lower the possibilitythat the execution of the predetermined processing will be interrupteddue to the power supply to the processing device being cut off.

Also, each processing device may further include a clock unit operableto measure an operating time of the own processing device in each ofpredetermined time periods and store therein the measured operatingtimes, each power information piece may include an operation history ofthe own processing device pertaining to the predetermined time periods,the detection subunit of the power information transmission unit maydetect a start of power supply to the own processing device, each timethe detection subunit performs the detection, the update subunit of thepower information transmission unit may update the operation history sothat the operating times of the own processing device in thepredetermined time periods stored by the clock unit are reflected in theoperation history, and the selection unit of the instructing device mayselect the processing device to be instructed to execute thepredetermined processing, in accordance with the operation historiesreceived by the power information reception unit of the instructingdevice.

According to this structure, each time the detection subunit of thepower information transmission unit performs the detection, the updatesubunit of the power information transmission unit updates the operationhistory so that the operating times in the predetermined time periodsstored by the clock unit are reflected in the operation history (e.g.,operation counts for each time period) in the power information.Therefore, if the selection unit of the instructing device selects theprocessing device that, for example, has the highest operation count inthe time period in which the predetermined processing is to be executedor an operation count in such time period that is higher than apredetermined reference count, it is possible to lower the possibilitythat the execution of the predetermined processing will be interrupteddue to the power supply to the processing device being cut off.

Also, the power information transmission unit of each processing devicemay include a storage subunit storing therein the power informationpiece relating to the own processing device, each power informationpiece may include a cut-ability information piece that is presetinformation for identifying whether a user can perform an operation tocut off power supply from an alternating current power supply to the ownprocessing device, and the selection unit of the instructing device mayselect the processing device to be instructed to execute thepredetermined processing, in accordance with the cut-ability informationpieces received by the power information reception unit of theinstructing device.

According to this structure, the power information transmission unit ofthe processing device transmits power information that includescut-ability information that identifies whether a user can perform anoperation to cut off the power supply from the alternating current powersupply to the processing device. Therefore, if the selection unit of theinstructing device selects, for example, a processing device whosecut-ability information indicates that such an operation cannot beperformed, it is possible to lower the possibility that the execution ofthe predetermined processing will be interrupted due to the power supplyto the processing device being cut off.

Also, the power information transmission unit of each processing devicemay include a storage subunit storing therein the power informationpiece relating to the own processing device, each power informationpiece may include an estimated value information piece that is presetinformation indicating an estimated value of a probability that a userhas performed an operation to cut off power supply from an alternatingcurrent power supply to the own processing device, and the selectionunit of the instructing device may select the processing device to beinstructed to execute the predetermined processing, in accordance withthe estimated value information pieces received by the power informationreception unit of the instructing device.

According to this structure, the power information transmission unit ofthe processing device transmits power information that includesestimated value information that is a preset estimated value indicatinga probability of a user cutting off the power supply from thealternating current power supply to the processing device. Therefore, ifthe selection unit of the instructing device selects, for example, aprocessing device whose estimate value information indicates a lowestestimated value or an estimated value that is less than a predeterminedspecified value, it is possible to lower the possibility that theexecution of the predetermined processing will be interrupted due to thepower supply to the processing device being cut off.

Also, the power information transmission unit of each processing devicemay include a storage subunit storing therein the power informationpiece relating to the own processing device, each power informationpiece may include a battery presence information piece that is presetinformation for identifying whether the own processing device includesan internal battery, and the selection unit of the instructing devicemay select the processing device to be instructed to execute thepredetermined processing, in accordance with the battery presenceinformation pieces received by the power information reception unit ofthe instructing device.

According to this structure, the power information transmission unit ofthe processing device transmits power information that includes batterypresence information that is preset information for identifying whetheran internal battery exists in the processing device. Therefore, if theselection unit of the instructing device selects, for example, aprocessing device whose battery present information indicates that aninternal battery is not present, it is possible to lower the possibilitythat the execution of the predetermined processing will be interrupteddue to exhaustion of the internal battery in the processing device.

Also, each processing device may further include an internal battery,the power information transmission unit of each processing device mayinclude a storage subunit storing therein the power information piecerelating to the own processing device, each power information piece mayinclude a maximum operating time that is preset information indicating amaximum battery-based operating time of the own processing device, andthe selection unit of the instructing device may select the processingdevice to be instructed to execute the predetermined processing, inaccordance with the maximum operating times received by the powerinformation reception unit of the instructing device.

According to this structure, the power information transmission unit ofthe processing device transmits power information that includes amaximum operating time that is preset information indicating a maximumtime for which the processing device can operate on the internalbattery. Therefore, if the selection unit of the instructing deviceselects, for example, a processing device whose maximum operating timeis longest or longer than a predetermined reference time, it is possibleto lower the possibility that the execution of the predeterminedprocessing will be interrupted, since there is an increased possibilityof the predetermined processing being continued on the power of theinternal battery even if the power supply from the alternating currentpower supply has been cut off.

Also, the instructing device and the processing devices may be connectedvia a LAN, the instructing device may further include a requestinformation transmission unit operable to broadcast, via the LAN,request information that requests transmission of the power informationpieces, each processing device may further include a request informationreception unit operable to receive the request information transmittedby the instructing device, and in each processing device, the powerinformation transmission unit may transmit the power information piecepertaining to the own processing device if the request informationreception unit has received the request information.

According to this structure, the power information transmission unit ofthe processing device transmits the power information if the requestinformation reception unit has received the request informationbroadcasted via the LAN by the instructing unit. Therefore, theinstructing device can acquire power information from a processingdevice newly connected to the LAN and loses the ability to acquire powerinformation from a processing device that has been disconnected from theLAN. In other words, this structure enables the instructing device toselect a processing device to be instructed to perform the predeterminedprocessing, based on power information from processing devices that areactually connected to the LAN.

Also, each processing device may further include a storage unit storingtherein information relating to a function included in the ownprocessing device, the request information may include functioninformation relating to a function necessary to execute thepredetermined processing, and in each processing device, the powerinformation transmission unit may transmit the power information piecepertaining to the own processing device if the information stored in thestorage unit includes the function information included in the requestinformation received by the request information reception unit.

According to this structure, the power information transmission unit ofthe processing device transmits the power information if the functioninformation included in the request information received by the requestinformation reception unit is included in the information pertaining tothe functions included in the processing device. This structure enablesthe instructing device to select a processing device to be instructed toexecute the predetermined processing, based on power information fromprocessing devices that can execute the predetermined processing.

Also, the instructing device and the processing devices may be connectedvia a LAN, each processing device may further include a detection unitoperable to detect a change in a state of power supply to the ownprocessing device, and in each processing device, the power informationtransmission unit may broadcast the power information piece pertainingto the own processing device via the LAN if the detection unit hasdetected a change in the state of power supply.

According to this structure, the power information transmission unit ofthe processing device broadcasts the power information via the LAN eachtime the detection unit has detected a change in the power supply state,that is to say, each time the detection unit has detected that, forexample, the power supply to the processing device has begun. Thisstructure enables the instructing device to select a processing deviceto be instructed to perform the predetermined processing, based on powerinformation from processing devices that are actually connected to theLAN.

Also, the information processing system may further include a powerinformation server, the instructing device may further include a requestinformation transmission unit operable to transmit, to the powerinformation server, request information that requests transmission ofthe power information pieces, and the power information server mayinclude a server power information reception unit operable to receivethe power information pieces transmitted by the power informationtransmission units of the processing devices; a request informationreception unit operable to receive the request information transmittedby the instructing device; and a server power information transmissionunit operable to, if the request information reception unit has receivedthe request information, transmit the power information pieces receivedby the server power information reception unit to the instructing devicethat transmitted the request information.

According to this structure, upon receiving the request information fromthe instructing device, the power information transmission unit of thepower information server transmits, to the instructing device, the powerinformation received from the processing devices by the powerinformation reception unit of the power information server. Thisstructure enables the instructing device to select a processing deviceto be instructed to perform the predetermined processing, based on powerinformation managed by the power information server.

Another aspect of the present invention is an instructing device thatinstructs any of a plurality of external devices to executepredetermined processing, the instructing device including: a powerinformation reception unit operable to receive a plurality of powerinformation pieces that are in one-to-one correspondence with theplurality of external devices, each power information piece relating topower supply of the corresponding external device and being stored bythe corresponding external device; a selection unit operable to select,from among the external devices, an external device to be instructed toexecute the predetermined processing, in accordance with the powerinformation pieces received by the power information reception unit; andan instruction transmission unit operable to transmit an instruction toexecute the predetermined processing to the external device selected bythe selection unit.

According to this structure, the selection unit of the instructingdevice selects the external device that is to be requested to executethe predetermined processing, based on power information relating to thepower supply to the external devices. Therefore, in a case where thepower information is information indicating the reliability of powersupply, such as information indicating whether the power supply cable ofthe external devices can be unplugged from the plug socket (the poweroutlet), selecting the external device that has a high power supplyreliability enables lowering the possibility that the execution of thepredetermined processing will be interrupted due to the power supply toan external device being cut off.

Also, the instructing device may further include: a storage unit storingtherein a criteria information table including (i) informationindicating types of processing in correspondence with (ii) powerinformation criteria information used when selecting the external deviceto be instructed to execute the corresponding type of processing,wherein the selection unit may acquire, from the criteria informationtable, power information criteria information that corresponds to thetype of the predetermined processing, and selects the external devicewhich holds the power information piece that satisfies the acquiredpower information criteria information.

According to this structure, the selection unit of the instructingdevice selects an external device that is holding power information thatsatisfies the power information criteria information, in the criteriainformation table, which corresponds to the type of the predeterminedprocessing, thereby enabling the instructing device to select theexternal device that satisfies the criteria for the required powersupply reliability corresponding to the type of the predeterminedprocessing.

Specifically, the power information indicates the reliability of powersupply by, for example, indicating whether the power cable of theexternal device can be unplugged from the power output, and the criteriainformation table includes criteria information indicating that theability to be unplugged from the power outlet is not permitted in thecase of processing during which an interruption must not occur (e.g.,real-time processing such as the reception of a TV program). In thiscase, the above structure enables the selection unit of the instructingdevice to select an external device that has a high power supplyreliability, that is to say satisfies the criteria informationindicating that the ability to be unplugged from the power output is notpermitted, as the external device to be instructed to execute thepredetermined processing during which an interruption must not occur.

Also, the instructing device may further include: a reception unitoperable to receive, from a user, power information criteria informationused when selecting the external device to be instructed to execute thepredetermined processing, wherein the selection unit may select theexternal device which holds the power information piece that satisfiesthe power information criteria information received by the receptionunit.

According to this structure, the selection unit of the instructingdevice selects the external device that holds power information thatsatisfies the criteria information received from the user, therebyenabling the instructing device to select the external device thatsatisfies the criteria reflecting the user's intention.

For example, if the power information indicates the reliability of powersupply, that is to say, whether the power cable of the external devicecan be unplugged from the power output, and the criteria informationreceived from the user indicates, for example, that the ability to beunplugged from the power outlet is not permitted in the case ofprocessing that is important to the user and during which aninterruption must not occur, the selection unit of the instructingdevice can select an external device that has a high power supplyreliability, that is to say satisfies the criteria informationindicating that the ability to be unplugged from the power output is notpermitted, as the external device to be instructed to execute thepredetermined processing.

Another aspect of the present invention is a processing device thatexecutes predetermined processing if an instruction to execute thepredetermined processing has been received from an external device, theprocessing device including: a storage unit storing therein powerinformation relating to the processing device; a detection unit operableto detect a change in a state of power supply to the processing device;an update unit operable to, each time the detection subunit detects achange in the state of power supply, update the power information storedin the storage unit so that a result of the detection is reflected inthe power information; and a transmission unit operable to transmit thepower information to the external device.

According to this structure, each time the detection unit of theprocessing device detects a change in the power supply state, the updateunit of the processing device performs an update to cause the detectionresult to be reflected in the power information, and the transmissionunit of the processing device transmits the updated power information.Therefore, in the exemplary case of the detection unit detecting thatthe power supply has been cut off and the power information indicatingthe number of times that the power supply has been cut off, if theexternal device transmits a processing execution instruction to aprocessing device whose number of times that the power supply has beencut off is lowest or less than a predetermined reference count, it ispossible to lower the possibility that the execution of thepredetermined processing will be interrupted due to the power supply tothe processing device being cut off.

Another aspect of the present invention is an information processingmethod used in an information processing system including an instructingdevice that instructs execution of predetermined processing and aplurality of processing devices that are able to execute thepredetermined processing, the information processing method includingthe following steps performed by the instructing device: receiving aplurality of power information pieces that are in one-to-onecorrespondence with the plurality of processing devices, each powerinformation piece relating to power supply of the correspondingprocessing device and being stored by the corresponding processingdevice; selecting, from among the processing devices, a processingdevice to be instructed to execute the predetermined processing, inaccordance with the power information pieces received in the powerinformation reception step; and transmitting an instruction to executethe predetermined processing to the processing device selected in theselection step, and the information processing method including thefollowing steps performed by each processing device: receiving theinstruction to execute the predetermined processing transmitted by theinstructing device; executing the predetermined processing if theinstruction to execute the predetermined processing has been received inthe instruction reception step; and transmitting the power informationpiece that relates to power supply to the own processing device.

Another aspect of the present invention is an information processingsystem including an instructing device that instructs execution ofpredetermined processing and a plurality of processing devices that areable to execute the predetermined processing, the instructing deviceincluding: a connection history information reception unit operable toreceive a plurality of connection history information pieces that are inone-to-one correspondence with the plurality of processing devices, eachconnection history information piece relating to a network connectionhistory of the corresponding processing device and being stored by thecorresponding processing device; a selection unit operable to select,from among the processing devices, a processing device to be instructedto execute the predetermined processing, in accordance with theconnection history information pieces received by the connection historyinformation reception unit; and an instruction transmission unitoperable to transmit an instruction to execute the predeterminedprocessing to the processing device selected by the selection unit, andeach processing device including: an instruction reception unit operableto receive the instruction to execute the predetermined processingtransmitted by the instructing device; an execution unit operable toexecute the predetermined processing if the instruction reception unithas received the instruction to execute the predetermined processing;and a connection history information transmission unit operable totransmit the connection history information piece that relates to thenetwork connection history of the own processing device.

According to this structure, the selection unit of the instructingdevice selects the processing device that is to be requested to executethe predetermined processing, based on the connection historyinformation relating to the network connection histories of theprocessing devices. Therefore, in a case of the connection historyinformation being information indicating the network connectionreliability, such as information indicating whether the network cablecan be unplugged from the network cable port, selecting the processingdevice that has a high network connection reliability enables loweringthe possibility that the execution of the predetermined processing willbe interrupted due to the network connection to the processing devicebeing cut off.

Another aspect of the present invention is an information processingmethod used in an information processing system including an instructingdevice that instructs execution of predetermined processing and aplurality of processing devices that are able to execute thepredetermined processing, the information processing method includingthe following steps performed by the instructing device: receiving aplurality of connection history information pieces that are inone-to-one correspondence with the plurality of processing devices, eachconnection history information piece relating to a network connectionhistory of the corresponding processing device and being stored by thecorresponding processing device; selecting, from among the processingdevices, a processing device to be instructed to execute thepredetermined processing, in accordance with the connection historyinformation pieces received in the connection history informationreception step; and transmitting an instruction to execute thepredetermined processing to the processing device selected in theselection step, and the information processing method including thefollowing steps performed by each processing device: receiving theinstruction to execute the predetermined processing transmitted by theinstructing device; executing the predetermined processing if theinstruction to execute the predetermined processing has been received inthe instruction reception step; and transmitting the connection historyinformation piece that relates to the network connection history of theown processing device.

Another aspect of the present invention is an information processingsystem including an instructing device that instructs execution ofpredetermined processing, a plurality of processing devices that areable to execute the predetermined processing, and a selection serverthat selects, from among the plurality of processing devices, aprocessing device to be instructed by the instructing device to executethe predetermined processing, the instructing device including: arequest information transmission unit operable to transmit, to theselection server, request information that requests selection of theprocessing device to be instructed to execute the predeterminedprocessing: a device information reception unit operable to receive,from the selection server, processing device information that identifiesthe processing device to be instructed to execute the predeterminedprocessing; and an instruction transmission unit operable to transmit aninstruction to execute the predetermined processing to the processingdevice indicated by the processing device information received by thedevice information reception unit, each processing device including: aninstruction reception unit operable to receive the instruction toexecute the predetermined processing transmitted by the instructingdevice; an execution unit operable to execute the predeterminedprocessing if the instruction reception unit has received theinstruction to execute the predetermined processing; and a powerinformation transmission unit operable to transmit, to the selectionserver, the power information piece that relates to power supply to theown processing device, and the selection server including: a requestinformation reception unit operable to receive the request informationtransmitted by the instructing device; a power information receptionunit operable to receive the power information pieces transmitted by theprocessing devices; a selection unit operable to, if the requestinformation reception unit has received the request information, select,from among the plurality of processing devices, the processing device tobe instructed by the instructing device to execute the predeterminedprocessing, in accordance with the power information pieces received bythe power information reception unit; and a device informationtransmission unit operable to transmit, to the instructing device, theprocessing device information that identifies the processing deviceselected by the selection unit.

According to this structure, the selection unit of the selection serverselects the processing device that is to be requested to execute thepredetermined processing by the instructing device, based on powerinformation relating to power supply received from the processingdevices. Therefore, in a case where the power information is informationindicating the reliability of power supply, such as informationindicating whether the power supply cable of the processing devices canbe unplugged from the plug socket, selecting the processing device thathas a high power supply reliability enables lowering the possibilitythat the execution of the predetermined processing will be interrupteddue to the power supply to the processing device being cut off.

Another aspect of the present invention is an information processingmethod used in an information processing system including an instructingdevice that instructs execution of predetermined processing, a pluralityof processing devices that are able to execute the predeterminedprocessing, and a selection server that selects, from among theplurality of processing devices, a processing device to be instructed bythe instructing device to execute the predetermined processing, theinformation processing method including the following steps performed bythe instructing device: transmitting, to the selection server, requestinformation that requests selection of the processing device to beinstructed to execute the predetermined processing: receiving, from theselection server, processing device information that identifies theprocessing device to be instructed to execute the predeterminedprocessing; and transmitting an instruction to execute the predeterminedprocessing to the processing device indicated by the processing deviceinformation received in the device information reception step, theinformation processing method including the following steps performed byeach processing device: receiving the instruction to execute thepredetermined processing transmitted by the instructing device;executing the predetermined processing if the instruction to execute thepredetermined processing has been received in the instruction receptionstep; and transmitting, to the selection server, the power informationpiece that relates to power supply to the own processing device, and theinformation processing method including the following steps performed bythe selection server: receiving the request information transmitted bythe instructing device; receiving the power information piecestransmitted by the processing devices; if the request information hasbeen received in the request information reception step, selecting, fromamong the plurality of processing devices, the processing device to beinstructed by the instructing device to execute the predeterminedprocessing, in accordance with the power information pieces received inthe power information reception step; and transmitting, to theinstructing device, the processing device information that identifiesthe processing device selected in the selection step.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a system structure of an information processing system 100according to embodiment 1;

FIG. 2 shows a functional structure of an instructing device 200;

FIG. 3 shows a functional structure of a processing device 300;

FIG. 4 shows a data structure and exemplary content of a providedfunction table 400;

FIG. 5 shows a data structure and exemplary content of a power supplyattribute table 500;

FIG. 6 shows a data structure and exemplary content of a criteriainformation table 600;

FIG. 7 is a flowchart showing processing performed by the instructingdevice 200 of embodiment 1 to select a cooperating device;

FIG. 8 shows a data structure and exemplary content of a power supplyattribute table 800;

FIG. 9 shows a data structure and exemplary content of a criteriainformation table 900;

FIG. 10 shows a functional structure of a processing device 1000;

FIG. 11 shows a data structure and exemplary content of a power supplyattribute table 1100;

FIG. 12 is a flowchart showing processing performed by the instructingdevice 200 of embodiment 2 to select a cooperating device;

FIG. 13 shows a functional structure of a processing device 1300;

FIG. 14 shows a data structure and exemplary content of a power supplyattribute table 1400;

FIG. 15 shows a functional structure of a processing device 1500;

FIG. 16 shows a data structure and exemplary content of a power supplyattribute table 1600;

FIG. 17 shows a functional structure of a processing device 1700;

FIG. 18 shows a data structure and exemplary content of a power supplyattribute table 1800;

FIG. 19 shows a functional structure of a processing device 1900;

FIG. 20 shows a data structure and exemplary content of operationhistory information 2000;

FIG. 21 shows a data structure and exemplary content of a power supplyattribute table 2100;

FIG. 22 is a flowchart showing update processing performed by an updateunit 1903;

FIG. 23 shows a system structure of an information processing system2300 according to embodiment 3;

FIG. 24 shows a functional structure of an instructing device 2400;

FIG. 25 shows a system structure of a selection server 2500;

FIG. 26 is a flowchart showing processing performed by the instructingdevice 2400 to transmit instruction data to a cooperating device; and

FIG. 27 is a flowchart showing processing performed by the selectionserver 2500 to select a cooperating device.

DESCRIPTION OF THE CHARACTERS

-   -   100, 2300 information processing system    -   112, 119 home network    -   113, 115 communication line    -   114 wide area network    -   200, 2400 instructing device    -   201, 2501 table information reception unit    -   202, 306, 2502 storage unit    -   203 human interface    -   204 analysis unit    -   205, 2401 execution control unit    -   206, 303, 1701 execution unit    -   207 instruction transmission unit    -   208, 301, 2506 network interface    -   210, 310, 2310 network    -   300, 1000, 1300, 1500, 1700, 1900 processing device    -   302 instruction reception unit    -   304, 1001, 1303, 1503, 1703, 1901 table information transmission        unit    -   305, 1304, 1902 detection unit    -   307 transmission unit    -   320 AC power supply    -   1002, 1305, 1504, 1704, 1903 update unit    -   1301, 1501 main power control unit    -   1302, 1702 flag information    -   1502, 1904 clock unit    -   2402 request information transmission unit    -   2403 device information reception unit    -   2500 selection server    -   2503 request information reception unit    -   2504 selection unit    -   2505 device information transmission unit

DETAILED DESCRIPTION OF THE INVENTION

Embodiments of the present invention are described below with referenceto the drawings.

Embodiment 1

Overview

An information processing system of embodiment 1 is an improvement on aconventional information processing system in which a plurality ofdevices connected to a network cooperatively process a processingrequest received from a user.

In the case of devices installed in general households etc., there is apossibility that users of the devices will turn off the main powerswitch of the devices, unplug the power cable, etc. at an arbitrarytiming. If such an operation is performed during cooperative processing,the cooperative processing will stop.

In view of this, the information processing system of the presentembodiment has a structure in which a device that has received aprocessing request from a user (hereinafter, called the “instructingdevice”) selects, from among other devices (hereinafter, called“processing devices”), a processing device (hereinafter, called the“cooperating device”) that is to be caused to perform processing incooperation with the instructing device. In the present embodiment, theinstructing device selects a processing device that satisfies a criteriafor a predetermined power supply reliability.

The instructing device stores information indicating functions includedin the processing devices (hereinafter, called the “provided functiontable”), information indicating the power supply reliability of theprocessing devices (hereinafter, called the “power supply attributetable”), and information indicating, for each function, a criteria forpower supply reliability that must be satisfied by the processing devicethat is to execute the function (hereinafter, called the “criteriainformation table”). The instructing device selects a cooperating devicebased on these tables. Note that the data constituting the tables iscollected from the processing devices by the instructing device.

Take the exemplary case in which a DVD/HDD recorder (the instructingdevice) receives, from a user, a processing request that is a request torecord a TV program being broadcast in a format compliant with the H.264standard (hereinafter, called the “H.264 format TV program”). If theDVD/HDD recorder lacks a tuner function for receiving the H.264 formatTV program, the DVD/HDD recorder references the provided function tableand selects all processing devices that have such a tuner function(e.g., digital TV receivers) as cooperating device candidates, thenreferences the criteria information table and acquires the criteria forpower supply reliability that must be satisfied by the processing devicethat is to execute the tuner function (e.g., a criteria such as notpermitting the selection of a processing device whose power cable can beunplugged), and then references the power supply attribute table andselects, from among the cooperating device candidates, a processingdevice that satisfies the acquired criteria for power supply reliabilityas the cooperating device.

Since TV programs are generally broadcast in real-time, if the powersupply to a processing device is cut off and the execution of the tunerfunction is interrupted, part of the TV program will not be receivedduring the interruption. In other words, the execution of the tunerfunction must not be interrupted.

In view of this, the instructing device selects, as the cooperatingdevice, a processing device that satisfies the criteria for power supplyreliability corresponding to the function to be executed by theprocessing device (hereinafter, called the “cooperative function”). Thisenables causing a cooperative function during which an interruption mustnot occur to be executed by a cooperating device that can be expected tohave a stable power supply, and lowers the possibility of aninterruption in cooperative processing due to the power supply to thecooperating device that is executing cooperative processing being cutoff.

Structure

Information Processing System Structure

First is a description of the structure of the information processingsystem of embodiment 1.

FIG. 1 shows a system structure of an information processing system 100of embodiment 1.

As shown in FIG. 1, a home network 112 in a household A is connected toa wide area network 114 via a communication line 113, and the wide areanetwork 114 is connected to a home network 119 in a household B via acommunication line 115. The communication lines 113 and 115 respectivelyconnect the home networks 112 and 119 to the wide area network 114 by aconnection scheme such as a telephone line connection, an optical lineconnection, or a wireless connection.

The home network 112 is a LAN (Local Area Network) installed in thehousehold A. Connected to the home network 112 are a TV receiver 101, aDVD/HDD recorder 102, a refrigerator 103, an air conditioner 104, anaudio device 105, a front door intercom 106, a surveillance camera 107,a telephone 108, a lighting device 109, a video camera 110, and apersonal computer 111, all of which are installed in the household A.

Connected to the wide area network 114 are a personal computer 116, amobile phone 117, and an automobile 118.

The home network 119 is a LAN installed in the household B. Connected tothe home network 119 are a TV receiver 120 and a DVD/HDD recorder 121,both of which are installed in the household B.

When any of the devices connected to the home network 112 or 119 or thewide area network 114 receive a processing request from a user, thedevice executes processing corresponding to the request in cooperationwith another device if necessary. All of the connected devices can beeither an instructing device or a processing device.

Instructing Device Structure

The following describes the functional structure of the instructingdevice.

FIG. 2 shows a functional structure of an instructing device 200.

As shown in FIG. 2, the instructing device 200 includes a tableinformation reception unit 201, a storage unit 202, a human interface203, an analysis unit 204, an execution control unit 205, an executionunit 206, an instruction transmission unit 207, and a network interface208.

Although not depicted in FIG. 2, the instructing device 200 alsoincludes a CPU (Central Processing Unit). The functions of the tableinformation reception unit 201, the analysis unit 204, the executioncontrol unit 205, the execution unit 206, and the instructiontransmission unit 207 are realized by causing the CPU to executeprograms stored in the storage unit 202. Note that the power informationreception unit of the present invention corresponds to the tableinformation reception unit 201, and the selection unit of the presentinvention corresponds to the execution control unit 205.

The table information reception unit 201 receives function informationand power information from the processing devices via the networkinterface 208. The function information received from each processingdevice indicates a device name identifying the processing device, andfunctions included in the processing device. The power informationreceived from each processing device indicates the power supplyreliability of the processing device. The table information receptionunit 201 causes the received function information and power informationto be respectively reflected in the later-described provided functiontable and power supply attribute table that are stored in the storageunit 202.

The storage unit 202 is a nonvolatile RAM (Random Access Memory). Thestorage unit 202 stores the provided function table, power supplyattribute table, and criteria information table that are used whenselecting a cooperating device, as well as function informationpertaining to the instructing device 200. The structures of the abovetables are described later.

The human interface 203 is an input/output device. The human interface203 receives a processing request from a user via an input device suchas a remote control, a keyboard, or a microphone, and sends the receivedprocessing request to the analysis unit 204. Additionally, the humaninterface 203 receives, from the execution control unit 205 describedlater, an execution result pertaining to the processing request receivedfrom the user, and outputs the execution result to an output device suchas a display, a speaker, a headphone, or an LED.

The analysis unit 204 analyzes the content of the processing requestreceived from the user via the human interface 203, and sends, to theexecution control unit 205, information indicating a function requiredto perform the processing corresponding to the processing request(hereinafter, called the “requested function information”).

The execution control unit 205 receives the requested functioninformation from the analysis unit 204, and based on the receivedrequested function information, judges whether cooperation with anotherprocessing device is necessary in order to execute the processingcorresponding to the processing request received from the user via thehuman interface 203.

Upon judging that cooperation with another processing device isnecessary, the execution control unit 205 selects a cooperating device,and sends, to the instruction transmission unit 207, a device name foridentifying the selected cooperating device and information indicating acooperative function to be executed by the cooperating device(hereinafter, called the “cooperative function information”).

The execution control unit 205 selects the cooperating device based onthe provided function table, power supply attribute table, and criteriainformation table that are stored in the storage unit 202. Specifically,the execution control unit 205 selects, as the cooperating device, aprocessing device that includes the cooperative function indicated bythe cooperative function information and furthermore satisfies thecriteria for power supply reliability that is required to execute thecooperative function.

Also, the execution control unit 205 controls the execution unit 206 toexecute any functions included in the own device that are indicated bythe requested function information, and sends, to the human interface203, an execution result pertaining to the processing corresponding tothe processing request received from the user.

In accordance with the control of the execution control unit 205, theexecution unit 206 executes the functions included in the own device andsends an execution result to the execution control unit 205. Forexample, if the instructing device 200 is a DVD/HDD recorder that has arecording function but lacks a tuner function for receiving an H.264format TV program, the execution unit 206 performs the recordingfunction by recording, to an HDD, H.264 format video data received viathe network interface 208 from a cooperating device that includes therequired tuner function.

Based on a device name and cooperative function information receivedfrom the execution control unit 205, the instruction transmission unit207 generates instruction data that instructs a cooperating device toexecute the cooperative function, and transmits the generatedinstruction data to the cooperating device via the network interface208.

The instruction data is command data for causing the execution of thecooperative function indicated by the cooperative function informationreceived from the execution control unit 205. If the cooperativefunction is, for example, a tuner function for receiving an H.264 formatTV program, the instruction data is command data that instructs thereception of the TV program and includes parameters such as informationspecifying the frequency (channel) for receiving the TV program andinformation specifying the broadcast time of the program.

The network interface 208 is an NIC (Network Interface Card) thatconnects with a network 210. Note that the network 210 is the homenetwork 112, the home network 119, or the wide area network 114 shown inFIG. 1.

Processing Device Structure

The following describes the functional structure of the processingdevices.

FIG. 3 shows a functional structure of a processing device 300.

As shown in FIG. 3, the processing device 300 includes a networkinterface 301, an instruction reception unit 302, an execution unit 303,and a table information transmission unit 304.

Although not depicted in FIG. 3, the processing device 300 also includesa CPU. The functions of the instruction reception unit 302, theexecution unit 303, and the table information transmission unit 304 arerealized by causing the CPU to execute programs stored in alater-described storage unit 306. Note that the power informationtransmission unit of the present invention corresponds to the tableinformation transmission unit 304.

The network interface 301 is an NIC that connects with a network 310.Note that the network 310 is the home network 112, the home network 119,or the wide area network 114 shown in FIG. 1.

The instruction reception unit 302 receives instruction data from theinstructing device 200 via the network interface 301, and sends thereceived instruction data to the execution unit 303.

Based on the instruction data received from the instruction receptionunit 302, the execution unit 303 executes a cooperative function andsends an execution result to the instructing device 200 via the networkinterface 301. For example, if the instruction data is command data forcausing the execution of a tuner function for receiving an H.264 formatTV program, the execution unit 303 receives a TV program in accordancewith a frequency (channel), broadcast time, etc. specified asparameters, and sends video data of the received TV program to theinstructing device 200 via the network interface 301.

The table information transmission unit 304 sends, to the instructingdevice 200 via the network interface 301, a device name identifying theprocessing device 300, function information indicating functionsincluded in the processing device 300, and power information indicatinga power supply reliability of the processing device 300. The tableinformation transmission unit 304 includes a detection unit 305, thestorage unit 306, and a transmission unit 307.

The detection unit 305 is a circuit for detecting that power is beingsupplied to the execution unit 303 from a commercial AC power supply 320via a power cable and a power outlet. In other words, the detection unit305 detects a startup of the processing device 300 and sends a detectionsignal to the transmission unit 307 each time the startup is detected.

The storage unit 306 is a ROM (Read Only Memory). The storage unit 306stores the device name, function information, and power information ofthe processing device 300, and destination information indicating anaddress for when the above information is transmitted by thetransmission unit 307. Note that the destination information has beenpreset by the user etc., and indicates an address, such as an IPaddress, of a device permits itself to be selected as a cooperatingdevice, that is to say, a device that permits cooperative processing.

The device name and function information stored in the storage unit 306of the processing device 300 are preset by a manufacturer etc. of theprocessing device 300. Also, the power information stored in the storageunit 306 of the processing device 300 is preset by the manufacturer etc.of the processing device 300 in view of the general usage of theprocessing device 300, or is set by an installer or user of theprocessing device 300 during installation, in view of the installationcondition and actual usage of the processing device.

Each time a detection signal is received from the detection unit 305,that is to say, each time the processing device 300 starts up, thetransmission unit 307 transmits the device name, function information,and power information stored in the storage unit 306, based on thedestination information stored in the storage unit 306, via the networkinterface 301.

Data

The following describes the tables used by the instructing device 200.

First is a description of the provided function table.

FIG. 4 shows a data structure and exemplary content of a providedfunction table 400.

As shown in FIG. 4, the provided function table 400 stored in thestorage unit 202 includes a device name 401 and a provided function 402in correspondence with each other for each processing device.

The device names 401 are processing device names for identifying theprocessing devices that are connected to the network. The device namesstored in the storage units 306 of the processing devices correspond tothe device names 401. The provided functions 402 indicate functionsincluded in the corresponding processing devices. The functioninformation stored in the storage units 306 of the processing devicescorresponds to the provided functions 402.

Taking one example from FIG. 4, the provided functions of the processingdevice having the device name “DEVICE A” are “MPEG2 decoder”, “MPEG2encoder”, and “Down convert”. In other words, the processing devicehaving the device name “DEVICE A” includes an MPEG2 decoder function, anMPEG2 encoder function, and an MPEG2 down conversion function. Also, theprovided functions of the processing device having the device name“DEVICE B” are “H.264 tuner”, “MPEG2 tuner”, “H.264 encoder”, and “MPEG2encoder”. In other words, the processing device having the device name“DEVICE B” includes an H.264 tuner function, an MPEG2 tuner function, anH.264 encoder function, and an MPEG2 encoder function.

The following describes updating of the provided function table 400.

Since each processing device transmits the device name and functioninformation stored in the storage unit 306 each time the processingdevice starts up, the table information reception unit 201 of theinstructing device 200 causes the received device names and functioninformation to be reflected in the provided function table 400.

Specifically, if the provided function table 400 does not have a recordincluding a device name 401 that matches the received device name, arecord composed of the received device name and function information isadded to the provided function table 400. If the provided function table400 has a record including a device name 401 that matches the receiveddevice name, but the provided function information 402 corresponding tothe record is different from the received function information, theprovided function 402 of the record is updated with the receivedfunction information.

Note that since each processing device transmits its device name andfunction information to the instructing device 200 each time theprocessing device starts up, periodically deleting the records in theprovided function table 400 achieves the deletion of records forprocessing devices that are no longer in use due to a malfunction etc.,that is to say, processing devices that are no longer connected to thenetwork. This enables keeping the provided function table 400 in anup-to-date state.

The following describes the power supply attribute table.

FIG. 5 shows a data structure and exemplary content of a power supplyattribute table 500.

As shown in FIG. 5, the power supply attribute table 500 stored in thestorage unit 202 includes a device name 501, an unpluggability 502, andan estimated unplugged probability 503 in correspondence with each otherfor each processing device.

The device names 501 are processing device names that correspond to thedevice names 401 in the provided function table 400 shown in FIG. 4.

The unpluggabilities 502 indicate whether the power cable of thecorresponding processing device can be unplugged from the power outlet.If a corresponding unpluggability 502 is “YES”, which indicates that thepower cable can be unplugged from the power outlet, the estimatedunplugged probability 503 indicates an estimated level of probabilitythat the power cable is unplugged. The power information stored in thestorage units 306 of the processing devices corresponds to theunpluggabilities 502 and estimated unplugged probabilities 503.

Taking one example from FIG. 5, the processing device whose device nameis “DEVICE A” has an unpluggability of “YES”, which indicates that thepower cable can be unplugged, and an estimated unplugged probability of“Low” (e.g., once in several months). One concrete example of the deviceA is a refrigerator, which is normally in use.

Taking another example from FIG. 5, the processing device whose devicename is “DEVICE C” has an unpluggability of “NO”, which indicates thatthe power cable cannot be unplugged. Concrete examples of the DEVICECare an AV device that is embedded in a wall and receives a constantpower supply from the commercial AC power supply 320, a front doorintercom, and a lighting device.

The following describes updating of the power supply attribute table500.

Similarly to the aforementioned device names and function information,since each processing device transmits the power information stored inthe storage unit 306 each time the processing device starts up, thetable information reception unit 201 of the instructing device 200causes the received device names and power information to be reflectedin the power supply attribute table 500.

Specifically, if the power supply attribute table 500 does not have arecord including a device name 501 that matches the received devicename, a record composed of the received device name and powerinformation is added to the power supply attribute table 500. If thepower supply attribute table 500 has a record including a device name501 that matches the received device name, but the unpluggability 502and estimated unplugged probability 504 corresponding to the record aredifferent from the received power information, the unpluggability 502and estimated unplugged probability 504 of the record are updated withthe received power information.

The following describes the criteria information table.

FIG. 6 shows a data structure and exemplary content of a criteriainformation table 600.

As shown in FIG. 6, the criteria information table 600 stored in thestorage unit 202 includes a function name 601, an unpluggabilitycriteria 602, and an estimated probability criteria 603 incorrespondence with each other for each cooperative function. Note thatthe criteria information table 600 stored in the storage unit 202 of theinstructing device 200 has been preset by a manufacturer etc. of theinstructing device 200.

The function names 601 are function names for identifying thecorresponding cooperative functions.

The unpluggability criteria 602 and estimated probability criteria 603indicate criteria for selecting a processing device that is to executethe corresponding cooperative function. Specifically, the unpluggabilitycriteria 602 indicates whether a processing device whose power cable canbe unplugged from a power outlet is permitted to be selected as theprocessing device that is to execute the corresponding cooperativefunction. The estimated probability criteria 603 indicates a permissibleunplugged probability level if the corresponding unpluggability criteria602 indicates that a processing device whose power cable can beunplugged from a power outlet is permitted to be selected.

In the exemplary case of the MPEG2 decoder cooperative function in FIG.6, the corresponding function name is “MPEG2 decoder”, theunpluggability criteria for the processing device that is execute theMPEG2 decoder function is “YES”, which indicates that a processingdevice whose power cable can be unplugged from a power outlet ispermitted to be selected, and the estimated probability criteria is“Normal or lower”, which indicates that an unplugged probability of, forexample, once a month or less is permissible.

In the exemplary case of the H.264 tuner cooperative function in FIG. 6,the corresponding function name is “H.264 tuner”, and the unpluggabilitycriteria for the processing device that is to execute the H.264 tunerfunction is “NO”, which indicates that a processing device whose powercable can be unplugged from a power outlet is not permitted to beselected.

Operations

The following describes operations of the instructing device 200 havingthe above structure and handling the above data.

FIG. 7 is a flowchart showing processing performed by the instructingdevice 200 to select a cooperating device.

The analysis unit 204 receives a processing request from the user viathe human interface 203, analyzes the content of the processing request,and sends, to the execution control unit 205, requested functioninformation indicating a function required to perform the processingcorresponding to the received processing request.

Upon receiving the requested function information from the analysis unit204, the execution control unit 205 judges whether cooperation withanother processing device is necessary to perform the processingcorresponding to the processing received from the user via the humaninterface 203 (step S701). Specifically, if all of the functionsindicated by the received requested function information are functionsindicated by the function information stored in the storage unit 202 ofthe own device, the execution control unit 205 judges that cooperationis not necessary. If any of the functions indicated by the receivedrequested function information are functions not indicated by thefunction information stored in the storage unit 202 of the own device,the execution control unit 205 judges that cooperation is necessary.

In a case of judging that cooperation with another processing device isnecessary (step S701:Y), the execution control unit 205 references theprovided function table 400 stored in the storage unit 202 and selectsall processing device that include the function not included in the owndevice (the cooperative function) as cooperating device candidates (stepS702), and then acquires the unpluggability criteria and estimatedprobability criteria for the processing device that is to execute thecooperative function from the criteria information table 600 stored inthe storage unit 202 (step S703).

The execution control unit 205 then references the power supplyattribute table 500 and, from among the cooperating device candidatesselected in step S702, selects, as the cooperating device, oneprocessing device that satisfies the unpluggability criteria andestimated probability criteria acquired in step S703 (step S704), andsends a device name identifying the selected cooperating device andcooperative function information indicating the cooperative function tothe instruction transmission unit 207.

Based on the device name and cooperative function information receivedfrom the execution control unit 205, the instruction transmission unit207 generates instruction data for instructing the cooperating deviceindicated by the device name to execute the cooperative function, andtransmits the generated instruction data to the cooperating device viathe network interface 208 (step S705). Note that information regardingthe necessary parameters is acquired from the analysis unit 204 whengenerating the instruction data. Information such as an IP addressindicating the recipient cooperating device is necessary in order totransmit the instruction data to the cooperating device. Thisinformation may be preset by the user etc., and may include a devicename and an address, such as an IP address, in correspondence with eachother for each processing device. Alternatively, since information suchas a transmission-source IP address is collected when device names etc.are received from the processing devices, such information may be usedwhen transmitting the instruction data.

The execution control unit 205 judges whether the own device includesthe functions required to perform the processing corresponding to theprocessing request received from the user (step S706). Specifically, ifa function indicated by the received requested function information is afunction indicated by the function information of the own device, theexecution control unit 205 judges that the own device includes arequested function that is to be executed.

Upon judging that the own device includes a function to be executed(step S706:Y), the execution control unit 205 causes the execution unit206 to execute the requested function (step S707), and ends theprocessing for selecting a cooperating device.

Upon judging in step S706 that the own device does not include any ofthe functions required to perform the processing corresponding to thereceived processing request (step S706:N), the execution control unit205 ends the processing for selecting a cooperating device.

If the execution control unit 205 judges in step S701 that cooperationwith another processing device is not necessary (step S701:N),processing proceeds to step S707.

Concrete Example of Operation

The following describes a concrete example of the operations of theinstructing device 200 with reference to FIG. 7, using the exemplarycontent of the provided function table 400 of FIG. 4, the power supplyattribute table 500 of FIG. 5, and the criteria information table 600 ofFIG. 6.

Note that in the following example, the instructing device 200 is aDVD/HDD recorder including a recording function and a playback function,and the instructing device 200 has received, from the user, a processingrequest that requests the recording of an H.264 format TV program.

The analysis unit 204 receives the processing request (the request torecord the H.264 format TV program) from the user via the humaninterface 203 of the instructing device 200, analyzes the content of theprocessing request, and sends, to the execution control unit 205,requested function information indicating functions required to performthe processing corresponding to the received processing request (anH.264 tuner function and a recording function).

Upon receiving the requested function information from the analysis unit204, the execution control unit 205 judges whether cooperation withanother processing device is necessary to perform the processingcorresponding to the processing request received from the user via thehuman interface 203 (step S701).

In this case, the execution control unit 205 judges that cooperation isnecessary (step S701:Y) since not all of the functions indicated by thereceived requested function information (the H.264 tuner function andthe recording function) are functions indicated by the functioninformation (the recording function and the playback function) stored inthe storage unit 202 of the own device, that is to say, since the H.264tuner function is not indicated by the function information of the owndevice. The execution control unit 205 then references the providedfunction table 400 stored in the storage unit 202 and selects allprocessing devices that include the cooperative function (the H.264tuner function) as cooperating device candidates (step S702).

The execution control unit 205 then acquires the unpluggability criteriaand estimated probability criteria for the processing device that is toexecute the cooperative function from the criteria information table 600stored in the storage unit 202 (step S703). Specifically, the executioncontrol unit 205 acquires the unpluggability criteria 602 “NO” (i.e., aprocessing device whose power cable can be unplugged from the poweroutlet is not permitted to be selected) corresponding to the cooperativefunction (the H.264 tuner function).

From among the cooperating device candidates (DEVICE B and DEVICE C)selected in step S702, the execution control unit 205 selects, as thecooperating device, a processing device (DEVICE C) whose upluggability502 in the power supply attribute table 500 satisfies the unpluggabilitycriteria 602 (“NO”) acquired in step S703 (step S704), and sends adevice name (DEVICE C) identifying the selected cooperating device andcooperative function information indicating the cooperative function(H.264 tuner) to the instruction transmission unit 207.

Based on the device name (DEVICE C) and cooperative function information(H.264 tuner) received from the execution control unit 205, theinstruction transmission unit 207 generates instruction data forinstructing the cooperating device indicated by the device name toexecute the cooperative function, and transmits the generatedinstruction data to the cooperating device via the network interface 208(step S705).

The execution control unit 205 judges whether the own device includesthe functions required to perform the processing corresponding to theprocessing request received from the user (step S706). Since a functionindicated by the function information of the own device (the recordingfunction) is one of the functions indicated by the received requestedfunction information (the H.264 tuner function and the recordingfunction), the execution control unit 205 judges that the own deviceincludes a requested function that is to be executed (step S706:Y), andcauses the execution unit 206 to execute the requested function (therecording function). With use of conventional technology for cooperativeprocessing between devices, the execution unit 206 performs processingfor recording, to an HDD (not depicted), H.264-compliant video data thatis received from the cooperating device (DEVICE C) (step S707),whereafter processing for selecting a cooperating device ends.

In this way, the instructing device 200 selects, as the cooperatingdevice, a processing device that satisfies the criteria for power supplyreliability corresponding to the cooperative function. This enablescausing a function during which an interruption in execution must notoccur, such as a tuner function, to be executed by a processing devicethat can be expected to have a stable power supply, and lowers thepossibility of an interruption in cooperative processing due to thepower supply to the cooperating device that is executing cooperativeprocessing being cut off.

Note that if a plurality of processing devices satisfy theunpluggability criteria and estimated probability criteria in step S704,an arbitrary one of the processing devices may be selected as thecooperating device. For example, if the processing devices “DEVICE A”and “DEVICE B”, which are first in the display order of device names assorted in the power supply attribute table 500, both satisfy theunpluggability criteria and estimated probability criteria, “DEVICE A”that is first in the display order may be selected as the cooperatingdevice.

Modification 1

Overview

In embodiment 1, the instructing device 200 selects the cooperatingdevice with use of the power supply attribute table 500, which includesthe unpluggabilities 502 indicating whether the power cable of thecorresponding processing device can be unplugged from the power outletand the estimated unplugged probabilities 503 indicating the estimatedlevel of probability that the power cable of the correspondingprocessing device is unplugged.

The following describes a modification in which the power supplyattribute table 500 has been replaced with a power supply attributetable composed of different items, focusing on differences fromembodiment 1.

Data

The following describes the power supply attribute table used by theinstructing device 200.

FIG. 8 shows a data structure and exemplary content of a power supplyattribute table 800.

As shown in FIG. 8, the power supply attribute table 800 stored in thestorage unit 202 of the instructing device 200 includes a device name501, a battery presence 801, and a maximum operating time 802 incorrespondence with each other for each processing device. A descriptionof the device names 501 has been omitted due to being the same as in thepower supply attribute table 500.

The battery presences 801 indicate whether the corresponding processingdevice includes an internal battery. The maximum operating times 802indicate the maximum operating time of the battery of the correspondingprocessing device, if the corresponding battery presence 801 is “YES”,that is to say, if the corresponding processing device includes abattery. The power information stored in the storage unit 306 of eachprocessing device has been preset by the manufacturer etc. of theprocessing device, and corresponds to the battery presences 801 andmaximum operating times 802.

Taking one example from FIG. 8, the processing device whose device nameis “DEVICE A” has a battery presence of “YES”, which indicates that abattery is included, and a battery-based maximum operating time of “1HOUR”. The processing device whose device name is “DEVICE C” has abattery presence of “NO”, which indicates that a battery is notincluded.

Note that a description of updating of the power supply attribute table800 has been omitted due to being similar to the updating of the powersupply attribute table 500.

The following describes the criteria information table.

FIG. 9 shows a data structure and exemplary content of a criteriainformation table 900.

As shown in FIG. 9, the criteria information table 900 stored in thestorage unit 202 includes a function name 601, a battery criteria 901,and a maximum operating time criteria 902 in correspondence with eachother for each cooperative function.

Note that the criteria information table 900 stored in the storage unit202 of the instructing device 200 has been preset by a manufacturer etc.of the instructing device 200. Also, a description of the function names601 has been omitted due to being the same as in the criteriainformation table 600.

The battery criteria 901 and maximum operating time criteria 902indicate criteria for selecting a processing device that is to executethe corresponding cooperative function. Specifically, the batterycriteria 901 indicates whether a processing device that includes abattery is permitted to be selected as the processing that is to executethe corresponding cooperative function. The maximum operating timecriteria 902 indicates a permissible battery-based maximum operatingtime if the corresponding battery criteria 901 indicates that aprocessing device including a battery is permitted to be selected.

In the exemplary case of the MPEG2 decoder cooperative function in FIG.9, the corresponding function name is “MPEG2 decoder”, the batterycriteria for the processing device that is to execute the MPEG2 decoderfunction is “YES”, which indicates that a processing device including abattery is permitted to be selected, and the permissible maximumoperating time is “2 hours or more”.

In the exemplary case of the H.264 tuner cooperative function in FIG. 9,the corresponding function name is “H.264 tuner”, and the batterycriteria for the processing device that is to execute the H.264 tunerfunction is “NO”, which indicates that a processing device including abattery is not permitted to be selected.

In a processing device that includes a battery and is operating on thebattery, cooperative processing will be interrupted if the battery runsout during the cooperative processing. Therefore, if a function duringwhich an interruption in execution must not occur, such as a tunerfunction, is caused to be executed by a processing device that does notinclude a battery, it is possible to prevent an interruption incooperative processing due to battery exhaustion, and lower thepossibility of an interruption in cooperative processing due to thepower supply to the cooperating device being cut off.

Also, in the case of causing a cooperative function to be executed by aprocessing device that includes a battery, if a processing device thathas a longer battery-based maximum operating time is selected as thecooperating device, it is possible to lower the possibility of batteryexhaustion during cooperative processing, and lower the possibility ofan interruption in cooperative processing due to battery exhaustion.

Embodiment 2

Overview

In embodiment 1, the processing device 300 transmits the powerinformation pre-stored in the storage unit 306 to the instructing device200.

In embodiment 2, each time the supply of power from a commercial ACpower supply to the execution unit 303 in a processing device isdetected, the processing device updates the power information stored inthe storage unit 306, and transmits the updated power information to aninstructing device of embodiment 2. The following description focuses ondifferences from embodiment 1.

Instructing Device Structure

First is a description of a functional structure of the instructingdevice of embodiment 2.

The instructing device 200 of embodiment 2 has basically the samestructure as the instructing device 200 of embodiment 1. However, theexecution control unit 205 in the instructing device 200 of embodiment 1selects a cooperating device based on the provided function table, powersupply attribute table, and criteria information table that are storedin the storage unit 202, while in contrast, the execution control unit205 in the instructing device 200 of embodiment 2 selects a cooperatingdevice based on only the provided function table and the power supplyattribute table. In other words, embodiment 2 differs from embodiment 1in that the criteria information table is not used when selecting acooperating device.

Processing Device Structure

Next is a description of a functional structure of a processing deviceof embodiment 2.

FIG. 10 shows a functional structure of a processing device 1000.

As shown in FIG. 10, the processing device 1000 includes the networkinterface 301, the instruction reception unit 302, the execution unit303, and a table information transmission unit 1001. The followingdescribes only the table information transmission unit 1001 since theother units are similar to the corresponding units in the processingdevice 300 of embodiment 1.

Note that although not depicted in FIG. 10, the processing device 1000includes a CPU. The functions of the table information transmission unit1001 are realized by causing the CPU to execute a program stored in thestorage unit 306.

The table information transmission unit 1001 has basically the samefunctions as the table information transmission unit 304 of embodiment1, with the exception that the table information transmission unit 1001has the ability to update the power information.

Specifically, the table information transmission unit 1001 includes thedetection unit 305, the storage unit 306, the transmission unit 307, andan update unit 1002. Descriptions of the units other the update unit1002 have been omitted since they are similar to the corresponding unitsof the table information transmission unit 304. However, each time powersupply is detected, the detection unit 305 of the table informationtransmission unit 1001 transmits the detection signal to the update unit1002 instead of the transmission unit 307.

Each time the detection signal is received from the detection unit 305,that is to say, each time power is supplied from the commercial AC powersupply 320 to the execution unit 303, the update unit 1002 incrementsthe power supply information stored in the storage unit 306 by one, thatis to say, increments by one the number of times that the power supplyfrom the commercial AC power supply 320 to the execution unit 303 hasbeen cut off. Here, the power information has an initial value of “0”,and is preset by the manufacturer etc. of the processing device 1000.

Data

The following describes the power supply attribute table used by theinstructing device 200 of embodiment 2.

FIG. 11 shows a data structure and exemplary content of a power supplyattribute table 1100.

As shown in FIG. 11, the power supply attribute table 1100 stored in thestorage unit 202 of the instructing device 200 of embodiment 2 includesa device name 501 and a cut-off count 1101 in correspondence with eachother for each processing device. A description of the device names 501has been omitted since they are the same as the device names 501 of thepower supply attribute table 500 shown in FIG. 5.

The cut-off count 1101 indicates the number of times that the powersupply from the commercial AC power supply 320 to the execution unit 303of the corresponding processing device has been cut off, that is to say,indicates the number of times that the power supply to the executionunit 303 has been cut off by the main power switch being turned off, thepower cable being unplugged, or the like. The power information storedin the storage unit 306 of each processing devices corresponds to thecut-off count 1101.

Taking one example from FIG. 11, the processing device whose device nameis “DEVICE A” has a power supply cut-off count of “17.4”, and theprocessing device whose device name is “DEVICE C” has a power supplycut-off count of “0”.

In other words, “DEVICE C”, in which the power supply from thecommercial AC power supply 320 to the execution unit 303 has been cutoff “0” times, can be expected to have a more stable power supply than“DEVICE A”. This shows that selecting “DEVICE C” as the cooperatingdevice enables lowering the possibility that cooperative processing willbe interrupted due to the power to the cooperating device being cut off.

Note that a description of updating of the power supply attribute table1100 has been omitted due to being similar to the updating of the powersupply attribute table 500.

Operations

The following describes operations of the instructing device 200 ofembodiment 2.

FIG. 12 is a flowchart showing processing performed by the instructingdevice 200 of embodiment 2 to select a cooperating device. Thecooperating device selection processing shown in FIG. 12 is the same asthe cooperating device selection processing shown in FIG. 7 andperformed by the instructing device 200 of embodiment 1, with theexception that steps S703 and S704 have been replaced with step S1201.Accordingly, the following describes only step S1201.

In step S1201, the execution control unit 205 in the instructing device200 of embodiment 2 references the power supply attribute table 1100and, from among the processing device candidates selected in step S702,selects, as the cooperating device, a processing device that has thelowest cut-off count 1101.

The following describes the processing of step S1201 using the exemplarycontent of the provided function table 400 shown in FIG. 4 and the powersupply attribute table 1100 shown in FIG. 11. Note that in step S702,the two processing devices whose device names are “DEVICE B” and “DEVICEC” have been selected as cooperating device candidates based on theprovided function table 400 shown in FIG. 4.

The execution control unit 205 in the instructing device 200 ofembodiment 2 references the power supply attribute table 1100 and, fromamong the processing device candidates (DEVICE B and DEVICE C) selectedin step S702, selects, as the cooperating device, the processing devicethat has the lowest cut-off count 1101 (DEVICE C) (step S1201).

In this way, the instructing device 200 of embodiment 2 selects theprocessing device whose power supply has been cut off the lowest numberof times from among the processing devices that include the cooperativefunction. This enables causing a function during which an interruptionin execution must not occur, such as a tuner function, to be executed bya cooperating device that can be expected to have a relatively stablepower supply, and lowers the possibility of an interruption incooperative processing due to the power supply to the cooperating devicethat is executing the cooperative function being cut off.

Although embodiment 2 describes an example of selecting a cooperatingdevice without using the criteria information table, it is of coursepossible to perform cooperating device selection processing that issimilar to the instructing device 200 of embodiment 1, by setting acriteria for a permissible cut-off count for each cooperative functionas a criteria information table of embodiment 2, and storing thecriteria information table in the storage unit 202 of the instructingdevice 200 of embodiment 2.

Modification 2

Overview

In embodiment 2, the update unit 1002 of the processing device loboupdates the number of times that the power supply to the execution unit303 has been cut off, each time the detection unit 305 detects that thepower supply to the execution unit 303 has been cut off by the mainpower switch being turned off, the power cable being unplugged, or thelike. In other words, the update unit 1002 updates the number of timesthat power supply has been cut off, without distinguishing between thecause for the power supply being cut off.

The following describes a modification in which the update unit 1002updates a different cut-off count for each cause for the power supply tothe execution unit 303 being cut off. The following description focuseson differences from embodiment 2. Note that the instructing device 200of modification 2 is the same as the instructing device 200 ofembodiment 2, with the exception of the content of the power supplyattribute table.

Processing Device Structure

First is a description of the functional structure of a processingdevice 1300 of modification 2.

FIG. 13 shows a functional structure of the processing device 1300.

As shown in FIG. 13, the processing device 1300 includes the networkinterface 301, the instruction reception unit 302, the execution unit303, a main power supply control unit 1301, and a table informationtransmission unit 1303. The following describes only the main powersupply control unit 1301 and table information transmission unit 1303since the other units are similar to the corresponding units in theprocessing device 1000 of embodiment 2.

Note that although not depicted in FIG. 13, the processing device 1300includes a CPU. The functions of the main power supply control unit 1301and table information transmission unit 1303 are realized by causing theCPU to execute programs stored in the storage unit 306.

The main power supply control unit 1301 controls whether power from thecommercial AC power supply 320 is supplied to the execution unit 303.

Specifically, the main power supply control unit 1301 includes auser-operable main power supply switch that, when pressed, switchesbetween a state in which power is supplied to the execution 303(hereinafter, called the “supply state”), and a state in which power isnot supplied to the execution unit 303 (hereinafter, called the “cut-offstate”). Also, the main power supply control unit 1301 stores flaginformation 1302 that identifies whether the current state is the supplystate or cut-off state, and updates the flag information 1302 toindicate the current state each time switching has been performed.

Note that even if the main power switch is pressed and the main powersupply control unit 1301 enters the cut-off state, power is suppliedfrom the commercial AC power supply 320 to the main power supply controlunit 1301 as long as the power cable of the processing device 1300remains inserted in the power outlet. Also, the flag information 1302 isset to indicate the cut-off state while the power cable of theprocessing device 1300 is inserted into the power outlet and the powersupply from the commercial AC power supply 320 to the main power supplycontrol unit 1301 is started.

The table information transmission unit 1303 has basically the samefunctions as the table information transmission unit 1001 of embodiment2, with the exception that the table information transmission unit 1303updates items in the power information according to the cause for thepower supply to the execution unit 303 being cut off.

The table information transmission unit 1303 includes the storage unit306, the transmission unit 307, a detection unit 1304, and an updateunit 1305. The following describes only the detection unit 1304 andupdate unit 1305 since the other units are similar to the correspondingunits of the table information transmission unit 1001.

The detection unit 1304 is a circuit that detects that power is beingsupplied from the commercial AC power supply 320 via the power cable andpower outlet, that is to say, detects that power is being supplied fromthe commercial AC power supply 320 due to the insertion of thepreviously unplugged power cable into the power outlet, and sends adetection signal to the update unit 1305 each time power supply isdetected.

The update unit 1305 judges the cause for the power supply to theexecution 303 being cut off according to whether the detection signal isbeing received from the detection unit 304 and according to changes inthe state of the main power supply control unit 1301 as indicated by theflag information 1302. In accordance with the cause for the power supplybeing cut off, the update unit 1305 updates the appropriate cut-offcount of the power information stored in the storage unit 306.

Specifically, if the flag information 1302 changes from the cut-offstate to the supply state while the detection signal is being receivedfrom the detection unit 1304, the update unit 1305 judges that the causefor the power supply being cut off is that the power cable has beenunplugged, and increments the AC power supply cut-off count in the powerinformation stored in the storage unit 306 by one. The AC power supplycut-off count indicates the number of times that the power cable hasbeen unplugged.

On the other hand, if the flag information 1302 changes from the cut-offstate to the supply state and the detection signal is not being receivedfrom the detection unit 1304, the update unit 1305 judges that the causefor the power supply being cut off is that the main power switch hasbeen turned off, and increments the main power supply cut-off count inthe power information stored in the storage unit 306 by one. The mainpower supply cut-off count indicates the number of times that the mainpower switch has been turned off.

Note that the AC power supply cut-off count and main power supplycut-off count have an initial value of “0”, and are preset by themanufacturer etc. of the processing device 1300.

Data

The following describes the power supply attribute table used by theinstructing device 200 of modification 2.

FIG. 14 shows a data structure and exemplary content of a power supplyattribute table 1400.

As shown in FIG. 14, the power supply attribute table 1400 stored in thestorage unit 202 of the instructing device 200 of modification 2includes a device name 501, an AC power supply cut-off count 1401, and amain power supply cut-off count 1402 in correspondence with each otherfor each processing device. A description of the device names 501 hasbeen omitted since they are the same as the device names 501 of thepower supply attribute table 1100 shown in FIG. 11.

The AC power supply cut-off count 1401 indicates the number of timesthat the power supply from the commercial AC power supply 320 to thecorresponding processing device has been cut off, that is to say, thenumber of times that the power supply has been cut off due to the powercable being unplugged. Also, the main power supply cut-off count 1402indicates the number of times that power supply to the execution unit303 in the corresponding processing device has been cut off due to themain power switch being turned off. The power information stored by thestorage unit 306 of each processing device corresponds to the AC powersupply cut-off count 1401 and main power supply cut-off count 1402.

Taking one example from FIG. 14, the processing device whose device nameis “DEVICE B” has an AC power supply cut-off count of “160”, that is tosay, the power supply has been cut off “160” times due to the powercable being unplugged, and has a main power supply cut-off count of“10”, that is to say, the power supply to the execution unit 303 hasbeen cut off “10” times due to the main power switch being turned off.

A processing device that has a high AC power supply cut-off count 1401,such as the processing device whose device name is “DEVICE B”, is aprocessing device on which a user frequently performs an operation thathas the danger of leading to a malfunction of the processing device,such as unplugging the power cable while the main power switch is in theON state.

In view of this, the processing device that has the lowest AC powersupply cut-off count 1401 can be expected to have a relatively stablepower supply. Selecting the processing device that has the lowest ACpower supply cut-off count 1401 as the cooperating device enablescausing a function during which an interruption in execution must notoccur, such as a tuner function, to be executed by a cooperating devicethat can be expected to have a relatively stable power supply, andlowers the possibility of an interruption in cooperative processing dueto the power supply to the cooperating device that is executing thecooperative function being cut off.

If a plurality of processing devices that have the same lowest AC powersupply cut-off count 1401 exist, the one of the these processing devicesthat has the lowest main power supply cut-off count 1402 is selected asthe cooperating device. This similarly lowers the possibility of aninterruption in cooperative processing due to the power supply to thecooperating device that is executing the cooperative function being cutoff.

Note that a description of updating of the power supply attribute table1400 has been omitted due to being similar to the updating of the powersupply attribute table 1100.

Modification 3

Overview

In modification 2, the power supply attribute table 1400 includes the ACpower supply cut-off counts 1401 that indicate the number of times thatthe power supply from the commercial AC power supply 320 to thecorresponding processing devices has been cut off and the main powersupply cut-off counts 1402 that indicate the number of times that powersupply to the execution unit 303 in the processing devices has been cutoff due to the main power switch being turned off.

The following describes a modification in which the main power supplycut-off count 1402 of the power supply attribute table 1400 has beenreplaced with the time for which the power supply to the execution unit303 has been cut off due to the main power switch being turned off(hereinafter, called the “main power supply cut-off time”. The followingdescription focuses on differences from modification 2. Note that theinstructing device 200 of modification 3 is the same as the instructingdevice 200 of modification 2, with the exception of the content of thepower supply attribute table.

Processing Device Structure

First is a description of the functional structure of a processingdevice 1500 of modification 3.

FIG. 15 shows a functional structure of the processing device 1500.

As shown in FIG. 15, the processing device 1500 includes the networkinterface 301, the instruction reception unit 302, the execution unit303, a main power supply control unit 1501, and a table informationtransmission unit 1503. The following describes only the main powersupply control unit 1501 and table information transmission unit 1503since the other units are similar to the corresponding units in theprocessing device 1300 of modification 2.

Note that although not depicted in FIG. 15, the processing device 1500includes a CPU. The functions of the main power supply control unit 1501and table information transmission unit 1503 are realized by causing theCPU to execute programs stored in the storage unit 306.

The main power supply control unit 1501 performs the functions of themain power supply control unit 1301 of modification 2, and additionallymeasures the main power supply cut-off time, which indicates the timefor which the power supply to the execution unit 303 has been cut offdue to the main power switch being turned off. The measuring of the mainpower supply cut-off time is realized by a clock unit 1502 included inthe main power supply control unit 1501. The clock unit 1502 is a timercircuit that measures an elapsed time beginning when the main powerswitch is turned off, that is to say, when the main power supply controlunit 1501 enters the cut-off state, and ending the next time the mainpower switch is operated by the user (turned on), that is to say, whenthe main power supply control unit 1501 enters the supply state.

The table information transmission unit 1503 has basically the samefunctions as the table information transmission unit 1303 ofmodification 2, with the exception that the table informationtransmission unit 1503 causes the power information to indicate the mainpower supply cut-off time measured by the clock unit 1502 of the mainpower supply control unit 1501.

The table information transmission unit 1503 includes the storage unit306, the transmission unit 307, the detection unit 1304, and an updateunit 1504. The following describes only the update unit 1504 since theother units are similar to the corresponding units of the tableinformation transmission unit 1303.

Instead of updating the main power supply cut-off count in the powerinformation like the update unit 1305 of modification 2, the update unit1504 updates the main power supply cut-off time in the powerinformation.

Specifically, upon judging that the power supply has been cut off due tothe main power switch being turned off, that is to say, in a case of theflag information 1302 changing from the cut-off state to the supplystate while the detection signal is not being received from thedetection unit 1304, the update unit 1504 acquires the main power supplycut-off time measured by the clock unit 1502, and adds the acquired mainpower supply cut-off time to the power information stored in the storageunit 306. Note that the main power supply cut-off time in the powerinformation has an initial value of “0”, and is preset by themanufacturer etc. of the processing device 1500.

Data

The following describes the power supply attribute table used by theinstructing device 200 of modification 3.

FIG. 16 shows a data structure and exemplary content of a power supplyattribute table 1600.

As shown in FIG. 16, the power supply attribute table 1600 stored in thestorage unit 202 of the instructing device 200 of modification 3includes a device name 501, an AC power supply cut-off count 1401, and amain power supply cut-off time 1601 in correspondence with each otherfor each processing device. A description of the device names 501 and ACpower supply cut-off counts 1401 has been omitted since they are thesame as the device names 501 and AC power supply cut-off counts 1401 ofthe power supply attribute table 1400 shown in FIG. 14.

The main power supply cut-off time 1601 indicates the time for which thepower supply to the execution unit 303 of the corresponding processingdevice has been cut off due to the main power switch being turned off.The power information stored by the storage unit 306 of each processingdevice corresponds to the AC power supply cut-off count 1401 and mainpower supply cut-off time 1601.

Taking one example from FIG. 16, the processing device whose device nameis “DEVICE A” has an AC power supply cut-off count of “0” and a mainpower supply cut-off time of “1000 HOURS”, that is to say, the powersupply to the execution unit 303 has been cut off for “1000 HOURS” dueto the main power switch being turned off.

A relatively stable power supply can be expected if the processingdevice that has the lowest AC power supply cut-off count 1401 and thelongest main power supply cut-off time, as in the processing devicewhose device name is “DEVICE A”, is selected to be the cooperatingdevice, thereby lowering the possibility of an interruption incooperative processing due to the power supply to the cooperating devicethat is executing the cooperative function being cut off. Furthermore,since the selected processing device has not been used by the user for arelatively long time, cooperative processing is performed efficiently byutilizing the surplus processing capacity of the selected processingdevice.

Note that a description of updating of the power supply attribute table1600 has been omitted due to being similar to the updating of the powersupply attribute table 1400.

Modification 4

Overview

In embodiment 2, the power supply attribute table 1100 includes thecut-off count 1101 that indicates the number of times that the powersupply has been cut off, regardless of whether the processing device1000 is executing a cooperative function.

The following describes a modification in which the cut-off count 1101of the power supply attribute table 1100 has been replaced with a countindicating the number of times that the power supply has been cut offduring the execution of a cooperative function (hereinafter, called the“mid-execution cut-off count”). The following description focuses ondifferences from embodiment 2. Note that the instructing device 200 ofmodification 4 is the same as the instructing device 200 of embodiment2, with the exception of the content of the power supply attributetable.

Processing Device Structure

First is a description of the functional structure of a processingdevice 1700 of modification 4.

FIG. 17 shows a functional structure of the processing device 1700.

As shown in FIG. 17, the processing device 1700 includes the networkinterface 301, the instruction reception unit 302, an execution unit1701, and a table information transmission unit 1703. The followingdescribes only the execution unit 1701 and table informationtransmission unit 1703 since the other units are similar to thecorresponding units in the processing device 1000 of embodiment 2.

Note that although not depicted in FIG. 17, the processing device 1700includes a CPU. The functions of the execution unit 1701 and tableinformation transmission unit 1703 are realized by causing the CPU toexecute programs stored in the storage unit 306.

The execution unit 1701 performs the functions of the execution unit 303of embodiment 2, and additionally identifies whether a cooperativefunction is being executed.

Specifically, the execution unit 1701 stores flag information 1702identifying whether a cooperative function is being executed. When acooperative function begins to be executed, the execution unit 1701updates the flag information 1702 to indicate a state in which acooperative function is being executed (hereinafter, called the“executing state”). When the execution of the cooperative function hasbeen completed, the execution unit 1701 updates the flag information1702 to indicate a state in which a cooperative function is not beingexecuted (hereinafter, called the “non-executing state”). Note that theflag information 1702 is stored in a non-volatile RAM included in theexecution unit 1701.

The table information transmission unit 1703 performs the functions ofthe table information transmission unit 1001 of embodiment 2, andadditionally updates the power information stored in the storage unit306 in accordance with the state of the execution unit 1701 indicated bythe flag information 1702.

Specifically, the table information transmission unit 1703 includes thedetection unit 305, the storage unit 306, the transmission unit 307, andan update unit 1704. The following describes only the update unit 1704since the other units are similar to the corresponding units of thetable information transmission unit 1001.

Each time a detection signal is received from the detection unit 305while the flag information 1702 of the execution unit 1701 indicates theexecuting state, the update unit 1704 increments the power informationwhich is the mid-execution cut-off count stored in the storage unit 306by one. Note that upon incrementing the power information which is themid-execution cut-off count by one, the update unit 1704 updates theflag information 1702 pertaining to the execution unit 1701 to indicatethe non-executing state. Also, the power information has an initialvalue of “0”, and is preset by the manufacturer etc. of the processingdevice 1700.

Data

The following describes the power supply attribute table used by theinstructing device 200 of modification 4.

FIG. 18 shows a data structure and exemplary content of a power supplyattribute table 1800.

As shown in FIG. 18, the power supply attribute table 1800 stored in thestorage unit 202 of the instructing device 200 of modification 4includes a device name 501 and a mid-execution cut-off count 1801 incorrespondence with each other for each processing device. A descriptionof the device names 501 has been omitted since they are the same as thedevice names 501 of the power supply attribute table 1100 shown in FIG.11.

The mid-execution cut-off count 1801 indicates the number of times thatthe power supply from the AC power supply 320 has been cut off while theexecution unit 303 of the corresponding processing device is executing acooperative function. The power information stored by the storage unit306 of each processing device corresponds to the mid-execution cut-offcount 1801.

Taking one example from FIG. 18, the processing device whose device nameis “DEVICE A” has a mid-execution cut-off count of “0”.

By selecting the processing device that has the lowest mid-executioncut-off count 1801 to be the cooperating device, a relatively stablepower supply can be expected during the execution of a cooperativefunction, thereby lowering the possibility of an interruption incooperative processing due to the power supply to the cooperating devicethat is executing the cooperative function being cut off.

Note that a description of updating of the power supply attribute table1800 has been omitted due to being similar to the updating of the powersupply attribute table 1400.

Modification 5

Overview

The following describes modification 5 in which the cut-off count 1101of the power supply attribute table 1100 of embodiment 2 has beenreplaced with an average operation time per day and a most-operationaltime period indicating a time period in which an operation count ishigh, with respect to a predetermined duration (e.g., the previous 7days) in each processing device. The following description focuses ondifferences from embodiment 2. Note that the instructing device 200 ofmodification 5 is the same as the instructing device 200 of embodiment2, with the exception of the content of the power supply attributetable.

Processing Device Structure

First is a description of the functional structure of a processingdevice 1900 of modification 5.

FIG. 19 shows a functional structure of the processing device 1900.

As shown in FIG. 19, the processing device 1900 includes the networkinterface 301, the instruction reception unit 302, the execution unit303, and a table information transmission unit 1901. The followingdescribes only the table information transmission unit 1901 since theother units are similar to the corresponding units in the processingdevice 1000 of embodiment 2.

Note that although not depicted in FIG. 19, the processing device 1900includes a CPU. The functions of the table information transmission unit1901 are realized by causing the CPU to execute a program stored in thestorage unit 306.

The table information transmission unit 1901 performs the functions ofthe table information transmission unit 1001 of embodiment 2, andadditionally updates the power information stored in the storage unit306. The power information includes an average operation time per dayand a most-operational time period indicating a time period in which theoperation count is high, with respect to a predetermined period (e.g.,the previous 7 days) in the processing device 1900. The tableinformation transmission unit 1901 updates the power information basedon times when the power supply to the execution unit 303 was started(hereinafter, called the “start times”) and times when the power supplyto the execution unit 303 was cut off (hereinafter, called the “endtimes”).

Specifically, the table information transmission unit 1901 includes thestorage unit 306, the transmission unit 307, a detection unit 1902, anupdate unit 1903, and a clock unit 1904. The following describes onlythe detection unit 1902, update unit 1903, and clock unit 1904 since theother units are similar to the corresponding units of the tableinformation transmission unit 1001. Note that even if the power supplyfrom the AC power supply 320 is cut off, the detection unit 1902, updateunit 1903, and clock unit 1904 receive a power supply from an internalbattery (not depicted) included in the processing device 1900.

The detection unit 1902 detects changes in the state of the power supplyfrom the AC power supply 320 to the execution unit 303. Specifically,the detection unit 1902 detects that the power supply to the executionunit 303 has started and that the power supply to the execution unit 303has been cut off, and sends a detection signal to the clock unit 1904each time either of the above is detected. When the start of the powersupply to the execution unit 303 has been detected, the detection unit1902 also sends the detection signal to the update unit 1903.

Each time the detection signal is received from the detection unit 1902,the clock unit 1904 stores the date and time of the detection, that isto say, stores start times and end times.

Each time the detection signal is received from the detection unit 1902,that is to say, each time the detection unit 1902 detects that the powersupply to the execution unit 303 has started, the update unit 1903calculates the operation time length and operation time periodpertaining to when the processing device 1900 previously operated, basedon the start time and end time of the previous operation instance storedin the clock unit 1904. The update unit 1903 then causes the calculatedoperation time length and operation time period to be reflected in thelater-described operation history information stored in the storage unit306. Also, the update unit 1903 updates the average operation time andmost-operational time period in the power information stored in thestorage unit 306, based on the operation history information.Furthermore, the average operation time and most-operational time periodin the power information have an initial value of “0”, and are preset bythe manufacturer etc. of the processing device 1900.

Data

The following describes the data used by the processing device 1900.

FIG. 20 shows a data structure and exemplary content of operationhistory information 2000.

As shown in FIG. 20, the operation history information 2000 stored inthe storage unit 306 of the processing device 1900 stores a date 2001,an operation time length 2002, and a time-period operation history 2003in correspondence with each other for each operation history of theprocessing device 1900.

The date 2001 is information indicating the date of a correspondingoperation history. The operation time length 2002 is informationindicating a total operation time of the processing device 1900 on acorresponding date. The time-period operation history 2003 isinformation indicating an operation state in each of 1-hour time periodson a corresponding date. A value of “1” recorded in a time period in thetime-period operation history 2003 indicates that the processing device1900 was operating in that time period.

Taking one example from FIG. 20, the operation time length of theprocessing device 1900 on the date “May 1, 2007” is “3 hours 57minutes”, and the time-period operation history shows that theprocessing device 1900 operated during the time periods “0:00-1:00”,“11:00-12:00”, and “12:00-13:00”.

The following describes the updating of the operation historyinformation 2000.

Each time the detection signal is received from the detection unit 1902,the update unit 1903 of the processing device 1900 calculates theoperation time length and operation time period pertaining to when theprocessing device 1900 previously operated, based on the start time andend time of the previous operation instance stored in the clock unit1904. The update unit 1903 then causes the calculated operation timelength and operation time period to be reflected in the operation timelength 2002 and time-period operation history 2003 pertaining to thecorresponding date.

Specifically, if the operation history information 2000 does not have arecord including a date 2001 indicating the date corresponding to thecalculated operation time length and operation time period, the updateunit 1903 adds a record including the date and calculated operation timelength and operation time. However, if such a record is already includedin the operation history information 2000, the update unit 1903 adds thecalculated operation time length to the operation time length 2002recorded in the record, and records a value of “1” in the time period ofthe time-period operation history 2003 that corresponds to thecalculated time period.

The following describes the updating of the power information stored inthe storage unit 306.

Each time the operation history information 200 is updated, the updateunit 1903 of the processing device 1900 calculates an average operationtime using the data from the operation time lengths 2002 pertaining tothe predetermined duration (e.g., the previous 7 days), and updates theaverage operation time in the power information stored in the storageunit 306 with the calculated average operation time. Also, the updateunit 1903 calculates a total operation count for each time period basedon the data from the time-period operation histories 2003 pertaining tothe predetermined duration, and updates the most-operational time periodin the power information with the time periods in which the operationcount is greater than or equal to a predetermined value (e.g., “3”).

The following describes the power supply attribute table used by theinstructing device 200 of modification 5.

FIG. 21 shows a data structure and exemplary content of a power supplyattribute table 2100.

As shown in FIG. 21, the power supply attribute table 2100 stored in thestorage unit 202 of the instructing device 200 of modification 5includes a device name 501, an average operation time 2101, and amost-operational time period 2102 in correspondence with each other foreach processing device. A description of the device names 501 has beenomitted since they are the same as the device names 501 of the powersupply attribute table 1100 shown in FIG. 11.

The average operation time 2101 is information indicating an averageoperation time per day in a predetermined duration (e.g., the previous 7days) in a corresponding processing device. The most-operational timeperiod 2101 is information indicating a time period in which the totaloperation count in the predetermined period is greater than or equal toa predetermined value (e.g., “3”). The power information stored by thestorage unit 306 of each processing device corresponds to the averageoperation time 2101 and most-operational time period 2102.

Taking one example from FIG. 21, the processing device whose device nameis “DEVICE A” has an average operation time of “2 hours 13 minutes” perday in the predetermined period (e.g., the previous 7 days), and themost-operational time period of “DEVICE A” in the predetermined periodis “11:00-13:00”. Also, the processing device whose device name is“DEVICE B” has an average operation time of “1 hour 18 minutes” per dayin the predetermined period, and the most-operational time period of“DEVICE B” in the predetermined period is “21:00-22:00”. Also, theprocessing device whose device name is “DEVICE D” has an averageoperation time of “7 hours 24 minutes” per day in the predeterminedperiod, and the most-operational time period of “DEVICE D” in thepredetermined period is “10:00-17:00”.

By selecting the processing device “DEVICE D”, which has the longestaverage operation time 2101 and the widest most-operational time period2102, to be the cooperating device, a relatively stable power supply canbe expected during the execution of a cooperative function, therebylowering the possibility of an interruption in cooperative processing.Even in the case of the processing device “DEVICE B” that has theshortest average operation time 2101, if the most-operational timeperiod of the processing device “DEVICE B” most closely matches the timeperiod in which the cooperative function is to be executed, selectingthe processing device “DEVICE B” to be the cooperating device enablesexpecting a relatively stable power supply during the execution of thecooperative function, thereby lowering the possibility of aninterruption in cooperative processing.

Note that a description of updating of the power supply attribute table2100 has been omitted due to being similar to the updating of the powersupply attribute table 1100.

Operations

The following describes operations of the processing device 1900 thathas the above-described structure and uses the above-described data.

FIG. 22 is a flowchart showing update processing performed by the updateunit 1903.

Upon receiving, the detection signal from the detection unit 1902 of theprocessing device 1900, the update unit 1903 of the processing device1900 acquires the start time and end time of the previous operationinstance stored in the clock unit 1904 of the processing device 1900(step S2201).

The update unit 1903 calculates an operation time length and anoperation time period based on the acquired start time and end time ofthe previous operation instance, causes the calculated operation timelength to be reflected in the operation time length 2002 of theoperation history information 2000 stored in the storage unit 306, andcauses the calculated operation time period to be reflected in thetime-period operation history 2003 of the operation history information2000 (step S2202).

The update unit 1903 calculates an average operation time based on thedata from the operation time lengths 2002 in the predetermined period(e.g., the previous 7 days) in the operation history information 2000,updates the average operation time in the power information with thecalculated average operation time, calculates a time period in which theoperation count is greater than or equal to the predetermined count(e.g., “3”) based on the data from the time-period operation histories2003 in the predetermined period, and updates the most-operational timeperiod in the power information with the calculated time period (stepS2203). The update unit 1903 then ends the update processing.

The following describes a concrete example of operations performed bythe processing device 1900 using the exemplary content of the operationhistory information 2000 shown in FIG. 20, with reference to FIG. 22.Let us assume that the operation history information 2000 shown in FIG.20 does not include a record for the date 2001 “May 7, 2007”, and thatthe clock unit 1904 of the processing device 1900 is storing a starttime “May 7, 2008, 10:58” and an end time “May 7, 2007, 12:08” for theprevious operation instance. Also, let us assume that the predeterminedperiod is the seven days of “May 1, 2007-May 7, 2007”, and that thepredetermined value is “3”.

Upon receiving the detection signal from the detection unit 1902 of theprocessing device 1900, the update unit 1903 of the processing device1900 acquires the start time (May 7, 2007, 10:58) and end time (May 7,2007 12:08) of the previous operation instance stored in the clock unit1904 of the processing device 1900 (step S2201).

The update unit 1903 calculates an operation time length (1 hour 10minutes) and an operation time period (11:00-12:00) based on theacquired start time and end time of the previous operation instance, andcauses the calculated operation time length and operation time period tobe reflected in the operation history information 2000 stored in thestorage unit 306 (step S2202). Specifically, since the operation historyinformation 2000 does not have a record including a date 2001 thatmatches the date (May 7, 2007) corresponding to the calculated operationtime length and operation time period, the update unit 1903 adds a date2001 of “May 7, 2007”, an operation time length 2002 of “1 hour 10minutes”, and a time-period operation history 2003 of “11:00-12:00”,that is to say, records a value of “1” in the 11:00-12:00 time period.

The update unit 1903 calculates an average operation time (2 hours 13minutes) based on the data from the operation time lengths 2002 in thepredetermined period (May 1, 2007-May 7, 2007) in the operation historyinformation 2000, updates the average operation time in the powerinformation with the calculated average operation time, calculates timeperiods (11:00-12:00 and 12:00-13:00, that is to say, 11:00-13:00) inwhich the operation count is greater than or equal to the predeterminedcount (“3”) based on the data from the time-period operation histories2003 in the predetermined period (May 1, 2007-May 7, 2007), and updatesthe most-operational time period in the power information with thecalculated most-operational time period (step S2203). The update unit1903 then ends the update processing.

Embodiment 3

Overview

In embodiment 1, the instructing device 200 selects a cooperating devicefrom among processing devices based on tables stored in the storage unit202.

An information processing system of embodiment 3 includes a selectionserver, and a cooperating device is selected from among processingdevices based on tables stored in the selection server. The followingdescription focuses on differences from embodiment 1.

Information Processing System Structure

First is a description of the structure of the information processingsystem of embodiment 3.

FIG. 23 shows a system structure of an information processing system2300 of embodiment 3.

As shown in FIG. 23, the information processing system 2300 includes aDVD/HDD recorder 2301, a DVD/HDD recorder 2302, a TV receiver 2303, a TVreceiver 2304, and a selection server 2500, all of which are connectedvia a network 2310.

The DVD/HDD recorders and TV receivers can be instructing devices andcooperating devices, and may be installed in the same household ordifferent locations. Also, the network 2310 is a network thatcorresponds to the home network 112, communication line 113, wide areanetwork 114, communication line 115, and home network 119, as shown inFIG. 1, in the information processing system 100 of embodiment 1.

Instructing Device Structure

The following describes the functional structure of the instructingdevice of embodiment 3.

FIG. 24 shows a functional structure of an instructing device 2400.

As shown in FIG. 24, the instructing device 2400 includes the humaninterface 203, the analysis unit 204, the execution unit 206, theinstruction transmission unit 207, the network interface 208, anexecution control unit 2401, a request information transmission unit2402, and a device information reception unit 2403.

The following describes only the execution control unit 2401, therequest information transmission unit 2402, and the device informationreception unit 2403 since the other units are similar to thecorresponding units in the instructing device 200 of embodiment 1.

Note that although not depicted in FIG. 24, the instructing device 2400includes a CPU. The functions of the execution control unit 2401, therequest information transmission unit 2402, and the device informationreception unit 2403 are realized by causing the CPU to execute programsstored in a memory.

The execution control unit 2401 has basically the same functions as theexecution control unit 205 of embodiment 1, with the exception that theexecution control unit 2401 does not select the cooperating device whencooperation with another processing device has been judged to benecessary.

Specifically, when cooperation with another processing device has beenjudged to be necessary, the execution control unit 2401 transmitscooperative function information indicating a cooperative function tothe request information transmission unit 2402, in order to cause theselection server 2500 to select a cooperating device.

The request information transmission unit 2402 generates requestinformation that requests the selection of a cooperating device andincludes the cooperative function information received from theexecution control unit 2401. The request information transmission unit2402 transmits the generated request information to the selection server2500 via the network interface 208.

The device information reception unit 2403 receives, from the selectionserver 2500, a device name identifying a cooperating device selected bythe selection server 2500 and information indicating an address, such asan IP address, of the selected cooperating device, and transfers thereceived device name and information indicating the address, such as anIP address, to the execution control unit 2401.

Selection Server Structure

The following describes the functional structure of the selectionserver.

FIG. 25 shows a system structure of the selection server 2500.

As shown in FIG. 25, the selection server 2500 includes a tableinformation reception unit 2501, a storage unit 2502, a requestinformation reception unit 2503, a selection unit 2504, a deviceinformation transmission unit 2505, and a network interface 2506.

Note that although not depicted in FIG. 25, the selection server 2500includes a CPU. The functions of the table information reception unit2501, request information reception unit 2503, selection unit 2504, anddevice information transmission unit 2505 are realized by causing theCPU to execute programs stored in the storage unit 2502. Note that thepower information reception unit of the present invention corresponds tothe table information reception unit 2501.

Similarly to the table information reception unit 201 of the instructingdevice 200 in embodiment 1, the table information reception unit 2501receives a device name, device information, and power information fromeach processing device via the network interface 2506, and causes thereceived device names, device information, and power information to bereflected in the provided function table 400 and power supply attributetable 500 stored in the storage unit 2502.

The storage unit 2502 is a nonvolatile RAM. Similarly to the store unit202 of the instructing device 200 in embodiment 1, the storage unit 2502stores the provided function table 400, the power supply attribute table500, and the criteria information table 600.

The request information reception unit 2503 receives request informationfrom the instructing device 2400 via the network interface 2506, andtransfers the received request information to the selection unit 2504.

The selection unit 2504 receives the request information from therequest information reception unit 2503, and based on the cooperativefunction information included in the received request information,selects, as the cooperating device, a processing device that theinstructing device 2400 will cause to execute a cooperative function.The selection unit 2504 then transmits a device name identifying theselected cooperating device to the device information transmission unit2505. Note that a description of the selection of the cooperating devicehas been omitted since, similarly to the execution control unit 205 ofthe instructing device 200 in embodiment 1, the selection of thecooperating device is performed based on the provided function table400, power supply attribute table 500, and criteria information table600 stored in the storage unit 2502.

The device information transmission unit 2505 receives the device nameof the cooperating device from the selection unit 2504, and transmitsthe device name and information indicating an address, such as an IPaddress, of the cooperating device to the instructing device 2400 viathe network interface 2506. Note that similarly to the instructiontransmission unit 207 of the instructing device 200 in embodiment 1, theinformation indicating the address, such as an IP address, of thecooperating device may be preset by the user etc., and indicate a devicename and an address, such as an IP address, in correspondence with eachother for each processing device, or may be information such as IPaddresses etc. indicating the transmission sources when the device namesetc. are received from the processing devices.

The network interface 2506 is an NIC that connects with the network2310.

Data

A description of the provided function table 400, power supply attributetable 500, and criteria information table 600 stored in the storage unit2502 of the selection server 2500 has been omitted since they aresimilar to the corresponding tables stored by the storage unit 202 ofthe instructing device 200 in embodiment 1. Note that the destinationinformation stored by the storage unit 306 of the processing device 300includes information indicating an address, such as an IP address, ofthe selection server.

Operations

Instructing Device Operations

The following describes operations performed by the instructing device2400.

FIG. 26 is a flowchart showing processing performed by the instructingdevice 2400 to transmit instruction data to a cooperating device. Theprocessing shown in FIG. 26 is the same as the processing shown in FIG.7 that is performed by the instructing device 200 of embodiment 1, withthe exception that steps S702 to S704 have been replaced with stepsS2601 and S2602. The following describes the processing of steps S2601and S2602.

If cooperation with another processing device is judged to be necessaryin step S701 (step S701:Y), the selection server 2500 is caused toselect a cooperating device by the following processing. The executioncontrol unit 2401 transmits cooperative function information indicatinga cooperative function to the request information transmission unit2402. The request information transmission unit 2402 generates requestinformation that requests the selection of a cooperating device andincludes the received cooperative function information, and transmitsthe generated request information to the selection server 2500 via thenetwork interface 208 (step S2601).

The device information reception unit 2403 receives a device name andinformation indicating an address such as an IP address from theselection server 2500 (step S2602), and transfers the received devicename and information indicating an address such as an IP address to theexecution control unit 2401. The execution control unit 2401 transmitsthe received device name, information indicating an address such as anIP address, and cooperative function information to the instructiontransmission unit 207, and thereafter ends processing.

Selection Server Operations

The following describes operations performed by the selection server2500.

FIG. 27 is a flowchart showing operations performed by the selectionserver 2500 to select a cooperating device.

The request information reception unit 2503 of the selection server 2500receives request information from the instructing device 2400 (stepS2701), and transfers the received request information to the selectionunit 2504. The selection unit 2504 receives the request information, andbased on the provided function table 400 stored in the storage unit2502, selects processing devices that include the cooperative functionindicated by the cooperative function information included in thereceived request information (step S2702).

Similarly to the processing of the instructing device 200 in embodiment1, the selection unit 2504 acquires an unpluggability criteria and anestimated probability criteria for the processing device that is toexecute the cooperative function (step S703), selects a cooperatingdevice (step S704), and transmits a device name identifying the selectedcooperating device to the device information transmission unit 2505.

The device information transmission unit 2505 receives the device nameof the cooperating device, and transmits the received device name andinformation indicating an address, such as an IP address, of thecooperating device to the instructing device 2400 (step S2703), andthereafter ends processing.

Supplementary Remarks

Although described above based on the embodiments, an informationprocessing system of the present invention is of course not limited tosuch embodiments. Variations such as the following are also possible.

(1) Although the execution of authentication processing when theinstructing device and cooperating device are to perform cooperativeprocessing is not particularly described in the above embodiments andmodifications, general authentication processing may be executed betweenthe instructing device and cooperating device.

(2) Although the provided function table and power supply attributetable are separate tables in the above embodiments and modifications,the provided function table and power supply attribute table may beintegrated in a single table. Specifically, taking the example ofembodiment 1, a device name, provided function, unpluggability, andestimated unplugged probability may be stored in a single table incorrespondence with each other for each processing device.

(3) Although the various devices are interconnected via a wired networkin the above embodiments and modifications, a wireless network or powerline network may be used. The same follows for the network 2310 ofembodiment 3.

Note that in the case of a power line network, both network connectionsand power supply to the devices and selection server are performed viapower cables, and therefore the power cable also functions as thenetwork interface in the instructive device, processing devices, andselection server.

(4) In the above embodiments and modifications, a home network may be aplurality of network groups connected by a router, bridge, or the like.Although the home network in the information system of embodiment 1 is anetwork installed in a household, the home network is not limited tobeing installed in a household. The home network may be installed in alocation such as an office.

(5) In the above embodiments and modifications, programs are stored inthe storage unit 202 of the instructing device, and part of thefunctions of the instructing device are realized by the CPU executingthe programs. However, the instructing device may include a memory thatis separate from the storage unit 202, and the programs may be stored inthe memory. The same follows for the programs stored in the storage unit306 of the processing device in the above embodiments and modifications.

(6) In the above embodiments and modifications, the instructing devicestores a provided function table indicating the functions included inthe various devices. However, if the various devices include the samefunctions, a provided performance table that indicates deviceperformance such as the CPU processing capability of each device may bestored instead of the provided function table. For example, if theinstructing device needs to perform cooperative processing with aprocessing device that includes two or more CPUs, the instructing devicemay reference the provided performance table and select, as cooperatingdevice candidates, cooperating devices that include two or more CPUs.

(7) In the above embodiments and modifications, the instructing deviceperforms cooperative processing with one processing device. However, inthe exemplary case of a plurality of cooperative functions to beexecuted, cooperative processing may be performed with a plurality ofprocessing devices. Even in the case of one cooperative function,conventional technology may be used to divide the cooperative functionamong a plurality of processing devices.

(8) Although the description in the above embodiments and modificationsfocuses on a case of the power supply to the processing device being cutoff during the execution of cooperative processing, an interruption incooperative processing may similarly occur if the network connection iscut off during the execution of cooperative processing. In view of this,a variation such as the following is also possible.

Specifically, instead of the power information, the processing devicesmay store connection history information indicating a network connectionhistory, the processing devices may transmit the connection historyinformation to the instructing device, and the instructing device mayselect a cooperating device based on the connection history informationreceived from the processing devices.

(9) The instructing device of embodiment 1 and modification 1 selects acooperating device with use of the criteria information table 600.However, in the example of embodiment 1, a cooperating device can beselected without using the criteria information table 600, by selectinga processing device whose unpluggability is “NO” to be the cooperatingdevice, regardless of the function that is to be executed by theprocessing device.

(10) In the description of the operations performed by the instructingdevice 200 of embodiment 1, H.264 format video data transmitted by theprocessing device 300 is received by the execution unit 206 of theinstructing device 200. However, the processing device 300 may encryptthe video data before transmission or convert (transcode) the video fromH.264 format to MPEG2 format before transmission.

(11) In the description of operations performed by the instructingdevice 200 of embodiment 1, the reception of a processing request from auser is used as the trigger for selecting a cooperating device. However,if the processing corresponding to the processing request from the useris processing whose execution is to be started at a predetermined time,such as scheduled recording to be performed by a DVD/HDD recorder, thearrival of the predetermined time may be used as the trigger forselecting a cooperating device.

(12) Although items in the power supply attribute table are simplyincreased in embodiment 2 and modifications 2 to 5, the items may beperiodically (e.g., once a month) reset to their initial values. Forexample, the cut-off counts 1101 in the power supply attribute table1100 of embodiment 2 may be reset once a month, thereby enabling theinstructing device to select a cooperating device based on the recentcut-off count trend of the processing devices.

Also, the processing device 1000 of embodiment 2 may store a history ofcut-off counts. Specifically, the processing device 100 may store a dateand a cut-off count in correspondence with each other for each history,and store cut-off counts in a predetermined duration (e.g., the previous30 or 31 days). This structure enables the instructing device to selecta cooperating device based on a recent cut-off count trend in theprocessing devices. The same follows for the processing devices ofmodifications 2 to 4.

(13) In embodiments 1 and 2 and modifications 1 to 5, the instructingdevice selects a cooperating device based on a prestored providedfunction table and power supply attribute table. However, if the variousdevices are physically connected via a single LAN (a LAN in the samesubnet), the instructing device does not need to prestore the providedfunction table and power supply attribute table. Specifically, uponjudging that cooperation with another processing device is necessary,the instructing device broadcasts, via the LAN, request information thatrequests the transmission of power information. In response to thereceived request information, the processing devices connected to theLAN transmit their device names, device information, and powerinformation. The instructing device selects a cooperating device basedon the device information and power information received from theprocessing devices.

Also, the instructing device may include cooperative functioninformation in the request information broadcasted via the LAN, andamong the processing devices that are connected to the LAN and receivedthe request information, only the processing devices that include thefunction indicated by the cooperative function information may transmittheir device name, device information, and power information.

Note that once device names, device information, and power informationhave been received from the processing devices, the instructing devicemay generate a provided function table and power supply attribute tablebased on the received information, and thereafter select a cooperatingdevice based on the generated tables. Also, after selecting acooperating device, the instructing device may discard the receivedinformation and perform the processing of broadcasting requestinformation and receiving information from the processing devices eachtime cooperation with another processing device becomes necessary.

(14) In embodiments 1 and 2 and modifications 1 to 5, the processingdevices transmit their device name, device information, and powerinformation in accordance with prestored information indicating anaddress such as an IP address. However, if the various devices arephysically connected via a single LAN (a LAN in the same subnet), theprocessing devices may broadcast their device names, device information,and power information via the LAN.

(15) Although the selection server 2500 selects a cooperating device inembodiment 3, the selection server may generate a provided functiontable and power supply attribute table based on the device names, deviceinformation, and power information received from the processing devices,and transmit the generated tables to the instructing device. Thereafter,the instructing device may select a cooperating device based on thetables received from the selection server.

(16) In embodiment 1, the instructing device 200 selects a cooperatingdevice based on the prestored criteria information table. However, theinstructing device 200 may receive, in advance from a user, a criteriafor selecting a processing device that is to execute a cooperativefunction, may be able to cause the received criteria to be reflected inthe criteria information table, and may select a cooperating devicebased on the criteria information table include the criteria receivedfrom the user.

Also, the processing request received from the user may be able tospecify a criteria for selecting a processing device that is to executea function corresponding to the processing request received from theuser, and the processing device may select a cooperating device based onthe criteria specified in the processing request.

(17) Embodiment 1 describes the operations of the instructing device 200using an exemplary case in which a DVD/HDD recorder (the instructingdevice 200) including a recording function and a playback functionselects a processing device including an H.264 tuner function to be thecooperating device. However, the present invention is of course notlimited to this example. Cooperative processing may be performed betweenall kinds of devices, examples of which include a TV receiver, anoptical disk (e.g., DVD or BD) recorder or player, a hard disk recordingdevice, a semiconductor memory recording device, an audio device, arefrigerator, an air conditioner, a front door intercom, a telephone, asurveillance camera, a lighting device, a video camera, a personalcomputer, a mobile phone, and an automobile.

For example, in order to prevent crime, a person away from home may wishto cause an appliance in his/her room to operate in order to make itappear as if the person were in his/her room. In this case, cooperativeprocessing may be performed between a mobile phone in the possession ofthe person and a processing device such as a TV receiver, an audiodevice, or a lighting fixture installed in the person's room (i.e., theprocessing device may be put into an operating state).

Also, since each processing device includes a CPU and the functions ofthe execution unit 303 are realized by the CPU executing a programstored in the storage unit 306, the instructing unit may, for example,cause a processing device to perform a desired function by transmittinga program for realizing a function when transmitting instruction data.This structure enables the instructing device to select a cooperatingdevice based on only the power supply attribute table, without givingconsideration to the functions included in the processing device.

INDUSTRIAL APPLICABILITY

An information processing system of the present invention is applicable,in a case where a plurality of devices perform processing incooperation, to selecting a device with which to cooperate.

1. An information processing system comprising: an instructing devicethat instructs execution of predetermined processing; and a plurality ofprocessing devices that are able to execute the predeterminedprocessing, wherein the instructing device includes: a power informationreception unit operable to receive a plurality of power informationpieces that are in one-to-one correspondence with the plurality ofprocessing devices, each power information piece relating to powersupply of the corresponding processing device and being stored by thecorresponding processing device; a selection unit operable to select,from among the processing devices, a processing device to be instructedto execute the predetermined processing, in accordance with the powerinformation pieces received by the power information reception unit; andan instruction transmission unit operable to transmit an instruction toexecute the predetermined processing to the processing device selectedby the selection unit, wherein each processing device includes: aninstruction reception unit operable to receive the instruction toexecute the predetermined processing transmitted by the instructingdevice; an execution unit operable to execute the predeterminedprocessing if the instruction reception unit has received theinstruction to execute the predetermined processing; and a powerinformation transmission unit operable to transmit the power informationpiece that relates to power supply to the own processing device, whereinthe power information transmission unit of each processing deviceincludes: a storage subunit storing therein the power information piecerelating to the own processing device; a detection subunit operable todetect a change in a state of power supply to the own processing device;and an update subunit operable to, each time the detection subunitdetects a change in the state of power supply, update the powerinformation piece stored in the storage subunit so that a result of thedetection is reflected in the power information piece, wherein if theupdate unit has updated the power information piece, the powerinformation transmission unit transmits the updated power informationpiece, wherein each power information piece includes a cut-off countindicating the number of times that power supply to the own processingdevice has been cut off, wherein the detection subunit of the powerinformation transmission unit detects a start of power supply to the ownprocessing device, wherein the update subunit of the power informationtransmission unit increments the cut-off count by one each time thedetection subunit performs the detection, and wherein the selection unitof the instructing device selects the processing device to be instructedto execute the predetermined processing, in accordance with the cut-offcounts received by the power information reception unit of theinstructing device.
 2. An information processing system comprising: aninstructing device that instructs execution of predetermined processing;and a plurality of processing devices that are able to execute thepredetermined processing, wherein the instructing device includes: apower information reception unit operable to receive a plurality ofpower information pieces that are in one-to-one correspondence with theplurality of processing devices, each power information piece relatingto power supply of the corresponding processing device and being storedby the corresponding processing device; a selection unit operable toselect, from among the processing devices, a processing device to beinstructed to execute the predetermined processing, in accordance withthe power information pieces received by the power information receptionunit; and an instruction transmission unit operable to transmit aninstruction to execute the predetermined processing to the processingdevice selected by the selection unit, wherein each processing deviceincludes: an instruction reception unit operable to receive theinstruction to execute the predetermined processing transmitted by theinstructing device; an execution unit operable to execute thepredetermined processing if the instruction reception unit has receivedthe instruction to execute the predetermined processing; and a powerinformation transmission unit operable to transmit the power informationpiece that relates to power supply to the own processing device, whereinthe power information transmission unit of each processing deviceincludes: a storage subunit storing therein the power information piecerelating to the own processing device; a detection subunit operable todetect a change in a state of power supply to the own processing device;and an update subunit operable to, each time the detection subunitdetects a change in the state of power supply, update the powerinformation piece stored in the storage subunit so that a result of thedetection is reflected in the power information piece, wherein if theupdate unit has updated the power information piece, the powerinformation transmission unit transmits the updated power informationpiece, wherein each processing device further includes a main powersupply control unit operable to (i) switch between a supply state ofsupplying power from an alternating current power supply to theexecution unit and a cut-off state of cutting off power from thealternating current power supply to the execution unit, and (ii)identify one of the supply state and the cut-off state, wherein eachpower information piece includes an alternating current power supplycut-off count indicating the number of times that power supply from thealternating current power supply to the own processing device has beencut off, wherein the detection subunit of the power informationtransmission unit detects a start of power supply from the alternatingcurrent power supply to the own processing device, wherein the updatesubunit of the power information transmission unit increments thealternating current power supply cut-off count by one each time thedetection subunit performs the detection while the main power supplycontrol unit is identifying the supply state, and wherein the selectionunit of the instructing device selects the processing device to beinstructed to execute the predetermined processing, in accordance withthe alternating current power supply cut-off counts received by thepower information reception unit of the instructing device.
 3. Theinformation processing system of claim 2, wherein the main power supplycontrol unit is further operable to measure a time during which thecut-off state is being identified, wherein each power information piecefurther includes a main power supply cut-off time indicating the timeduring which the main power supply control is identifying the cut-offstate, wherein each time the main power supply control unit switchesfrom the cut-off state to the supply state while the detection subunithas not performed the detection, the update subunit of the powerinformation transmission unit adds, to the main power supply cut-offtime, the time measured by the main power supply control unit, andwherein the selection unit of the instructing device selects theprocessing device to be instructed to execute the predeterminedprocessing, further in accordance with the main power supply cut-offtimes received by the power information reception unit of theinstructing device.
 4. An information processing system comprising: aninstructing device that instructs execution of predetermined processing;and a plurality of processing devices that are able to execute thepredetermined processing, wherein the instructing device includes: apower information reception unit operable to receive a plurality ofpower information pieces that are in one-to-one correspondence with theplurality of processing devices, each power information piece relatingto power supply of the corresponding processing device and being storedby the corresponding processing device; a selection unit operable toselect, from among the processing devices, a processing device to beinstructed to execute the predetermined processing, in accordance withthe power information pieces received by the power information receptionunit; and an instruction transmission unit operable to transmit aninstruction to execute the predetermined processing to the processingdevice selected by the selection unit, wherein each processing deviceincludes: an instruction reception unit operable to receive theinstruction to execute the predetermined processing transmitted by theinstructing device; an execution unit operable to execute thepredetermined processing if the instruction reception unit has receivedthe instruction to execute the predetermined processing; and a powerinformation transmission unit operable to transmit the power informationpiece that relates to power supply to the own processing device, whereinthe power information transmission unit of each processing deviceincludes: a storage subunit storing therein the power information piecerelating to the own processing device; a detection subunit operable todetect a change in a state of power supply to the own processing device;and an update subunit operable to, each time the detection subunitdetects a change in the state of power supply, update the powerinformation piece stored in the storage subunit so that a result of thedetection is reflected in the power information piece, wherein if theupdate unit has updated the power information piece, the powerinformation transmission unit transmits the updated power informationpiece, wherein each processing device further includes a main powersupply control unit operable to (i) switch between a supply state ofsupplying power from an alternating current power supply to theexecution unit and a cut-off state of cutting off power from thealternating current power supply to the execution unit, and (ii)identify one of the supply state and the cut-off state, wherein eachpower information piece includes a main power supply cut-off countindicating the number of times that power supply has been cut off by theswitching performed by the main power supply control unit, wherein thedetection subunit of the power information transmission unit detects astart of power supply from the alternating current power supply to theown processing device, wherein each time the main power supply controlunit switches from the cut-off state to the supply state while thedetection subunit has not performed the detection, the update subunit ofthe power information transmission unit increments the main power supplycut-off count by one, and wherein the selection unit of the instructingdevice selects the processing device to be instructed to execute thepredetermined processing, in accordance with the main power supplycut-off counts received by the power information reception unit of theinstructing device.
 5. An information processing system comprising: aninstructing device that instructs execution of predetermined processing;and a plurality of processing devices that are able to execute thepredetermined processing, wherein the instructing device includes: apower information reception unit operable to receive a plurality ofpower information pieces that are in one-to-one correspondence with theplurality of processing devices, each power information piece relatingto power supply of the corresponding processing device and being storedby the corresponding processing device; a selection unit operable toselect, from among the processing devices, a processing device to beinstructed to execute the predetermined processing, in accordance withthe power information pieces received by the power information receptionunit; and an instruction transmission unit operable to transmit aninstruction to execute the predetermined processing to the processingdevice selected by the selection unit wherein each processing deviceincludes: an instruction reception unit operable to receive theinstruction to execute the predetermined processing transmitted by theinstructing device; an execution unit operable to execute thepredetermined processing if the instruction reception unit has receivedthe instruction to execute the predetermined processing; and a powerinformation transmission unit operable to transmit the power informationpiece that relates to power supply to the own processing device, whereinthe power information transmission unit of each processing deviceincludes: a storage subunit storing therein the power information piecerelating to the own processing device; a detection subunit operable todetect a change in a state of power supply to the own processing device;and an update subunit operable to, each time the detection subunitdetects a change in the state of power supply, update the powerinformation piece stored in the storage subunit so that a result of thedetection is reflected in the power information piece, wherein if theupdate unit has updated the power information piece, the powerinformation transmission unit transmits the updated power informationpiece, wherein the execution unit of each processing device is furtheroperable to identify whether the predetermined processing is beingexecuted, wherein each power information piece includes a mid-executioncut-off count indicating the number of times that power supply to theown processing device has been cut off while the execution unit isexecuting the predetermined processing, wherein the detection subunit ofthe power information transmission unit detects a start of power supplyto the own processing device, wherein the update subunit of the powerinformation transmission unit increments the mid-execution cut-off countby one each time the detection subunit performs the detection while theexecution unit is executing the predetermined processing, and whereinthe selection unit of the instructing device selects the processingdevice to be instructed to execute the predetermined processing, inaccordance with the mid-execution cut-off counts received by the powerinformation reception unit of the instructing device.
 6. An informationprocessing system comprising: an instructing device that instructsexecution of predetermined processing; and a plurality of processingdevices that are able to execute the predetermined processing, whereinthe instructing device includes: a power information reception unitoperable to receive a plurality of power information pieces that are inone-to-one correspondence with the plurality of processing devices, eachpower information piece relating to power supply of the correspondingprocessing device and being stored by the corresponding processingdevice; a selection unit operable to select, from among the processingdevices, a processing device to be instructed to execute thepredetermined processing, in accordance with the power informationpieces received by the power information reception unit; and aninstruction transmission unit operable to transmit an instruction toexecute the redetermined processing to the processing device selected bythe selection unit wherein each processing device includes: aninstruction reception unit operable to receive the instruction toexecute the predetermined processing transmitted by the instructingdevice; an execution unit operable to execute the predeterminedprocessing if the instruction reception unit has received theinstruction to execute the predetermined processing; and a powerinformation transmission unit operable to transmit the power informationpiece that relates to power supply to the own processing device, whereinthe power information transmission unit of each processing deviceincludes: a storage subunit storing therein the power information piecerelating to the own processing device; a detection subunit operable todetect a change in a state of power supply to the own processing device;and an update subunit operable to, each time the detection subunitdetects a change in the state of power supply, update the powerinformation piece stored in the storage subunit so that a result of thedetection is reflected in the power information piece, wherein if theupdate unit has updated the power information piece, the powerinformation transmission unit transmits the updated power informationpiece, wherein each processing device further includes a clock unitoperable to measure a time during which the own processing device isoperating and store therein the measured time, wherein each powerinformation piece includes an average operation time of the ownprocessing device with respect to a predetermined duration, wherein thedetection subunit of the power information transmission unit detects astart of power supply to the own processing device, wherein each timethe detection subunit performs the detection, the update subunit of thepower information transmission unit updates the average operation timeso that the time stored by the clock unit is reflected in the averageoperation time, and wherein the selection unit of the instructing deviceselects the processing device to be instructed to execute thepredetermined processing, in accordance with the average operation timesreceived by the power information reception unit of the instructingdevice.
 7. An information processing system comprising: an instructingdevice that instructs execution of predetermined processing; and aplurality of processing devices that are able to execute thepredetermined processing, wherein the instructing device includes: apower information reception unit operable to receive a plurality ofpower information pieces that are in one-to-one correspondence with theplurality of processing devices, each power information piece relatingto power supply of the corresponding processing device and being storedby the corresponding processing device; a selection unit operable toselect, from among the processing devices, a processing device to beinstructed to execute the predetermined processing, in accordance withthe power information pieces received by the power information receptionunit; and an instruction transmission unit operable to transmit aninstruction to execute the redetermined processing to the processingdevice selected by the selection unit, wherein each processing deviceincludes: an instruction reception unit operable to receive theinstruction to execute the predetermined processing transmitted by theinstructing device; an execution unit operable to execute thepredetermined processing if the instruction reception unit has receivedthe instruction to execute the predetermined processing; and a powerinformation transmission unit operable to transmit the power informationpiece that relates to power supply to the own processing device, whereinthe power information transmission unit of each processing deviceincludes: a storage subunit storing therein the power information piecerelating to the own processing device; a detection subunit operable todetect a change in a state of power supply to the own processing device;and an update subunit operable to, each time the detection subunitdetects a change in the state of power supply, update the powerinformation piece stored in the storage subunit so that a result of thedetection is reflected in the power information piece, wherein if theupdate unit has updated the power information piece, the powerinformation transmission unit transmits the updated power informationpiece, wherein each processing device further includes a clock unitoperable to measure an operating time of the own processing device ineach of predetermined time periods and store therein the measuredoperating times, wherein each power information piece includes anoperation history of the own processing device pertaining to thepredetermined time periods, wherein the detection subunit of the powerinformation transmission unit detects a start of power supply to the ownprocessing device, wherein each time the detection subunit performs thedetection, the update subunit of the power information transmission unitupdates the operation history so that the operating times of the ownprocessing device in the predetermined time periods stored by the clockunit are reflected in the operation history, and wherein the selectionunit of the instructing device selects the processing device to beinstructed to execute the predetermined processing, in accordance withthe operation histories received by the power information reception unitof the instructing device.
 8. An information processing systemcomprising: an instructing device that instructs execution ofpredetermined processing; and a plurality of processing devices that areable to execute the predetermined processing, wherein the instructingdevice includes: a power information reception unit operable to receivea plurality of power information pieces that are in one-to-onecorrespondence with the plurality of processing devices, each powerinformation piece relating to power supply of the correspondingprocessing device and being stored by the corresponding processingdevice; a selection unit operable to select, from among the processingdevices, a processing device to be instructed to execute thepredetermined processing, in accordance with the power informationpieces received by the power information reception unit; and aninstruction transmission unit operable to transmit an instruction toexecute the redetermined processing to the processing device selected bythe selection unit, wherein each processing device includes: aninstruction reception unit operable to receive the instruction toexecute the predetermined processing transmitted by the instructingdevice; an execution unit operable to execute the predeterminedprocessing if the instruction reception unit has received theinstruction to execute the predetermined processing; and a powerinformation transmission unit operable to transmit the power informationpiece that relates to power supply to the own processing device, whereinthe power information transmission unit of each processing deviceincludes a storage subunit storing therein the power information piecerelating to the own processing device, wherein each power informationpiece includes a cut-ability information piece that is presetinformation for identifying whether a user can perform an operation tocut off power supply from an alternating current power supply to the ownprocessing device, and wherein the selection unit of the instructingdevice selects the processing device to be instructed to execute thepredetermined processing, in accordance with the cut-ability informationpieces received by the power information reception unit of theinstructing device.
 9. An information processing system comprising: aninstructing device that instructs execution of predetermined processing;and a plurality of processing devices that are able to execute thepredetermined processing, wherein the instructing device includes: apower information reception unit operable to receive a plurality ofpower information pieces that are in one-to-one correspondence with theplurality of processing devices, each power information piece relatingto power supply of the corresponding processing device and being storedby the corresponding processing device; a selection unit operable toselect, from among the processing devices, a processing device to beinstructed to execute the predetermined processing, in accordance withthe power information pieces received by the power information receptionunit; and an instruction transmission unit operable to transmit aninstruction to execute the predetermined processing to the processingdevice selected by the selection unit, wherein each processing deviceincludes: an instruction reception unit operable to receive theinstruction to execute the predetermined processing transmitted by theinstructing device; an execution unit operable to execute thepredetermined processing if the instruction reception unit has receivedthe instruction to execute the predetermined processing; and a powerinformation transmission unit operable to transmit the power informationpiece that relates to power supply to the own processing device, whereinthe power information transmission unit of each processing deviceincludes a storage subunit storing therein the power information piecerelating to the own processing device, wherein each power informationpiece includes an estimated value information piece that is presetinformation indicating an estimated value of a probability that a userhas performed an operation to cut off power supply from an alternatingcurrent power supply to the own processing device, and wherein theselection unit of the instructing device selects the processing deviceto be instructed to execute the predetermined processing, in accordancewith the estimated value information pieces received by the powerinformation reception unit of the instructing device.
 10. An informationprocessing system comprising: an instructing device that instructsexecution of predetermined processing; and a plurality of processingdevices that are able to execute the predetermined processing, whereinthe instructing device includes: a power information reception unitoperable to receive a plurality of power information pieces that are inone-to-one correspondence with the plurality of processing devices, eachpower information piece relating to power supply of the correspondingprocessing device and being stored by the corresponding processingdevice; a selection unit operable to select, from among the processingdevices, a processing device to be instructed to execute thepredetermined processing, in accordance with the power informationpieces received by the power information reception unit; and aninstruction transmission unit operable to transmit an instruction toexecute the redetermined processing to the processing device selected bythe selection unit, wherein each processing device includes: aninstruction reception unit operable to receive the instruction toexecute the predetermined processing transmitted by the instructingdevice; an execution unit operable to execute the predeterminedprocessing if the instruction reception unit has received theinstruction to execute the predetermined processing; and a powerinformation transmission unit operable to transmit the power informationpiece that relates to power supply to the own processing device, whereinthe power information transmission unit of each processing deviceincludes a storage subunit storing therein the power information piecerelating to the own processing device, wherein each power informationpiece includes a battery presence information piece that is presetinformation for identifying whether the own processing device includesan internal battery, and wherein the selection unit of the instructingdevice selects the processing device to be instructed to execute thepredetermined processing, in accordance with the battery presenceinformation pieces received by the power information reception unit ofthe instructing device.
 11. An information processing system comprising:an instructing device that instructs execution of predeterminedprocessing; and a plurality of processing devices that are able toexecute the predetermined processing, wherein the instructing deviceincludes: a power information reception unit operable to receive aplurality of power information pieces that are in one-to-onecorrespondence with the plurality of processing devices, each powerinformation piece relating to power supply of the correspondingprocessing device and being stored by the corresponding processingdevice; a selection unit operable to select, from among the processingdevices, a processing device to be instructed to execute thepredetermined processing, in accordance with the power informationpieces received by the power information reception unit; and aninstruction transmission unit operable to transmit an instruction toexecute the redetermined processing to the processing device selected bythe selection unit, wherein each processing device includes: aninstruction reception unit operable to receive the instruction toexecute the predetermined processing transmitted by the instructingdevice; an execution unit operable to execute the predeterminedprocessing if the instruction reception unit has received theinstruction to execute the predetermined processing; and a powerinformation transmission unit operable to transmit the power informationpiece that relates to power supply to the own processing device, whereineach processing device further includes an internal battery, wherein thepower information transmission unit of each processing device includes astorage subunit storing therein the power information piece relating tothe own processing device, wherein each power information piece includesa maximum operating time that is preset information indicating a maximumbattery-based operating time of the own processing device, and whereinthe selection unit of the instructing device selects the processingdevice to be instructed to execute the predetermined processing, inaccordance with the maximum operating times received by the powerinformation reception unit of the instructing device.
 12. An informationprocessing system comprising: an instructing device that instructsexecution of predetermined processing; and a plurality of processingdevices that are able to execute the predetermined processing, whereinthe instructing device includes: a power information reception unitoperable to receive a plurality of power information pieces that are inone-to-one correspondence with the plurality of processing devices, eachpower information piece relating to power supply of the correspondingprocessing device and being stored by the corresponding processingdevice; a selection unit operable to select, from among the processingdevices, a processing device to be instructed to execute thepredetermined processing, in accordance with the power informationpieces received by the power information reception unit; and aninstruction transmission unit operable to transmit an instruction toexecute the redetermined processing to the processing device selected bythe selection unit, wherein each processing device includes: aninstruction reception unit operable to receive the instruction toexecute the predetermined processing transmitted by the instructingdevice; an execution unit operable to execute the predeterminedprocessing if the instruction reception unit has received theinstruction to execute the predetermined processing; and a powerinformation transmission unit operable to transmit the power informationpiece that relates to power supply to the own processing device, whereinthe information processing system further comprises a power informationserver, wherein the instructing device further includes a requestinformation transmission unit operable to transmit, to the powerinformation server, request information that requests transmission ofthe power information pieces, and wherein the power information serverincludes: a server power information reception unit operable to receivethe power information pieces transmitted by the power informationtransmission units of the processing devices; a request informationreception unit operable to receive the request information transmittedby the instructing device; and a server power information transmissionunit operable to, if the request information reception unit has receivedthe request information, transmit the power information pieces receivedby the server power information reception unit to the instructing devicethat transmitted the request information.